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Development Models (development + models)
Selected AbstractsTime Development Models for Perfusion Provocations Studied with Laser-Doppler Flowmetry, Applied to Iontophoresis and PORHMICROCIRCULATION, Issue 7 2009Frits F.M. De Mul ABSTRACT Objective: Clinical acceptance of laser-Doppler perfusion monitoring (LDPM) of microcirculation suffers from lack of quantitatively reliable signal data, due to varying tissue constitution, temperature, hydration, etc. In this article, we show that a novel approach using physiological models for response upon provocations provides quantitatively and clinically relevant time constants. Methods: We investigated this for two provocation protocols: postocclusive reactive hyperemia (PORH) and iontophoresis shots, measured with LDPM on extremities. PORH experiments were performed on patients with peripheral arterial occlusive disease (PAOD) or diabetes mellitus (DM), and on healthy controls. Iontophoresis experiments were performed on pre-eclamptic patients and healthy controls. We developed two dynamical physical models, both based on two characteristic time constants: for PORH, an "arterial" and a "capillary" time constant and, for iontophoresis, a "diffusion" and a "decay" time constant. Results: For the different subject groups, we could extract time constants that could probably be related to physiological differences. For iontophoresis, a shot saturation constant was determined, with very different values for different groups and administered drugs. Conclusions: With these models, the dynamics of the provocations can be investigated and quantitative comparisons between experiments and subject groups become available. The models offer a quantifiable standard that is independent of the type of LDPM instrumentation. [source] PHILANTHROPY AND ENTERPRISE IN THE BRITISH CREDIT UNION MOVEMENTECONOMIC AFFAIRS, Issue 2 2005Paul A. Jones Through the 1990s hundreds of credit unions were established to serve indebted communities throughout Britain. These volunteer-run financial co-operatives did not meet growth expectations because of restrictive legislation, inadequate development models and well-intentioned but unproductive state intervention. British credit unions are more successful when they develop as market-oriented social enterprises able to build effective partnerships with banks, government and the private sector to serve low-income communities. [source] Open source in Swedish companies: where are we?INFORMATION SYSTEMS JOURNAL, Issue 6 2010Björn Lundell Abstract Open Source (OS) is a phenomenon of increasing significance for organizations, offering the prospect of effective alternative business solutions and new business opportunities. A number of surveys have been conducted in various countries with the purpose of understanding the state of practice with respect to OS in companies. In this paper we report on a study of the perceptions of OS and the uptake of OS products and development models in Swedish companies. The study used purposeful sampling of companies that have an expressed interest in OS, and the survey was conducted using a set of pre-prepared questions. Its goal was to investigate the extent to which OS has influenced business thinking, as seen from the standpoint of stakeholders. We found that uptake is much higher than reported in earlier studies, but as with previous studies, activity is still concentrated in small and medium-sized enterprises (SMEs). There is increased evidence of interest beyond the simple use of OS components at the infrastructure level. Further, a significant proportion of the companies studied are supporting the OS community as well as benefiting from it. Support includes participation in existing projects and the release of new software under OS licenses. [source] Brain networks: Graph theoretical analysis and development modelsINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2010Myoung Won Cho Abstract A trendy method to understand the brain is to make a map representing the structural network of the brain, also known as the connectome, on the scale of a brain region. Indeed analysis based on graph theory provides quantitative insights into general topological principles of brain network organization. In particular, it is disclosed that typical brain networks share the topological properties, such as small-world and scale-free, with many other complex networks encountered in nature. Such topological properties are regarded as characteristics of the optimal neural connectivity to implement efficient computation and communication; brains with disease or abnormality show distinguishable deviations in the graph theoretical analysis. Considering that conventional models in graph theory are, however, not adequate for direct application to the neural system, we also discuss a model for explaining how the neural connectivity is organized. © 2010 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 20, 108,116, 2010 [source] Exogenous Shocks or Endogenous Constructions?INTERNATIONAL STUDIES QUARTERLY, Issue 4 2007Crises, The Meanings of Wars This symposium addresses the role of wars and crises as mechanisms of international change. Over the past two decades, the international system has undergone a number of remarkable transformations, from the end of the Cold War to the emergence of an ongoing "War on Terror," and from the collapse of statist development models to the emergence of a contested,if evolving,neoliberal "Washington Consensus." This volatility exceeds any underlying shifts in economic structures or the distribution of capabilities, and raises important questions regarding the roles of agency, uncertainty, and ideas in advancing change. In this introduction we examine the role of wars and economic crises as socially constructed openings for change. We attempt three things: to critique materialist approaches in the security and political economy issue areas, to outline the distinctive contribution that an agent-centered constructivist understanding of such events offers, and to offer a framework for the study of such events, one which highlights an expanded range of elite-mass interactions. [source] Development's invisible hands: Introduction to special issueJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 6 2009Alan Thomas Abstract This Special Issue comes from the Development Studies Association (DSA) 30th Anniversary conference in 2008. The theme was ,Development's Invisible Hands', focusing on the forces likely to influence global change and re-shape development agendas over the next 30 years. The first section comprises brief invited thinkpieces mainly from DSA past presidents. Interestingly, while some focus on Adam Smith's original ,invisible hand' analogy and others discuss a range of non-market issues, several invoke Karl Polanyi on the limitations of market society. The second and third sections consist, respectively, of ,synthesis' papers on parallel panel themes and papers developed from the best panel presentations. The papers demonstrate the range of issues raised by questioning the future of development and development studies,while the limitations of future gazing are pointed up by the unexpected challenge to current development models presented since the conference by the global financial crisis. Copyright © 2009 John Wiley & Sons, Ltd. [source] The credit crunch , the right time for credit unions to strike?LEGAL STUDIES, Issue 1 2009Dr Nicholas Ryder The origins of the cooperative movement can be traced to the Rochdale Society of Equitable Pioneers in 1844, from which similar institutions emerged in Central Europe, the North American continent and the rest of the world. Modern credit unions evolved from these small cooperative societies and have developed into mainstream providers of financial services in many jurisdictions. However, credit unions in the UK have not made a similar impact. There are several factors that have limited their growth , an inadequate legislative framework, an ineffective credit union regulatory system, inappropriate development models, an over-reliance on state subsidies and a disunited movement. The aim of this paper is to re-examine these factors in light of the level of political support provided by the government since 1997. [source] Data quality in thermal summation development models for forensically important blowfliesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2009C. S. RICHARDS Abstract. To highlight some issues regarding data quality that are significant in estimating post-mortem intervals (PMI) from maggots, the developmental constants of thermal summation models for development of Chrysomya megacephala Fabricius (Diptera: Calliphoridae) were calculated from incidental data gathered from 12 published studies, and from data generated specifically for the purpose in a single experiment. The focused experiment involved measuring the timing of five developmental landmarks at nine constant temperatures with a sampling resolution of 6,12 h, which is characteristic of other published studies. Combining data from different studies produced inconsistent results because of statistical noise introduced by (at least) disparities in temporal precision, descriptive statistics, geographical location and rearing diets. A robust experimental design to estimate a developmental model should involve at least six constant temperatures, starting at about 7°C above the relevant developmental zero (D0) and going almost to the upper critical temperature, and a temporal sampling interval with a relative precision of about 10%, which requires sampling about every 2 h until hatching, about every 3 h until first ecdysis and about every 6 h until second ecdysis. [source] Natural resources and ,gradual' reform in Uzbekistan and TurkmenistanNATURAL RESOURCES FORUM, Issue 4 2003Richard Auty Abstract Among low-income transition reformers, natural resource rents are an important initial condition that helps explain choice of reform strategy. Resource-rich Uzbekistan and Turkmenistan and resource-poor China and Vietnam all claim to pursue gradual reform, but their strategies differ. In China and Vietnam, low resource rents have nurtured developmental political conditions and encouraged efficient resource use, which initially promoted agriculture as a dynamic market sector, capable of absorbing labour from the lagging state sector. In contrast, the scale and ease of natural resource rent extraction in the Central Asian countries has consolidated authoritarian governments that postpone reform. Despite high energy rents, Uzbekistan and Turkmenistan still extract agricultural rents in ways that repress farm incentives, perpetuate environmental degradation and liquidate irrigation assets. Uzbekistan uses its rents to subsidize a manufacturing sector, that is neither dynamic nor competitive. As its dynamic sector, Turkmenistan promotes natural gas exports that depend on volatile markets. Resource-driven development models suggest that reform is required in both countries to avert a growth collapse. Turkmenistan's large energy rent-stream may postpone a collapse for some years, but Uzbekistan's position is already precarious: it has run down its rural infrastructure and accumulated sizeable foreign debts and will require external assistance to recover from a growth collapse. Such assistance should be made conditional on accelerated economic and political reform. [source] Product and process innovation in biopharmaceuticals: a new perspective on developmentR & D MANAGEMENT, Issue 1 2006Lisa P. L. Lim Developing new products and processes is increasingly a focal point of competition and often requires the development and successful implementation of novel process technologies. The process development and production of a new biological entity are significantly more complex than those for small molecule drugs. Conventional new product development models in the literature on firm level innovation fail to explain the nature of development projects for biopharmaceuticals. This paper makes the case that a new perspective is required to understand the management of product and process development in biopharmaceuticals. An explanatory model is proposed for this purpose. [source] Identification and targeting of cancer stem cellsBIOESSAYS, Issue 10 2009Tobias Schatton Abstract Cancer stem cells (CSC) represent malignant cell subsets in hierarchically organized tumors, which are selectively capable of tumor initiation and self-renewal and give rise to bulk populations of non-tumorigenic cancer cell progeny through differentiation. Robust evidence for the existence of prospectively identifiable CSC among cancer bulk populations has been generated using marker-specific genetic lineage tracking of molecularly defined cancer subpopulations in competitive tumor development models. Moreover, novel mechanisms and relationships have been discovered that link CSC to cancer therapeutic resistance and clinical tumor progression. Importantly, proof-of-principle for the potential therapeutic utility of the CSC concept has recently been provided by demonstrating that selective killing of CSC through a prospective molecular marker can inhibit tumor growth. Herein, we review these novel and translationally relevant research developments and discuss potential strategies for CSC-targeted therapy in the context of resistance mechanisms and molecular pathways preferentially operative in CSC. [source] Experimental glaucoma development in albine rabbitsACTA OPHTHALMOLOGICA, Issue 2007N GUERRI Purpose: To compare four different glaucoma development models in albine rabbits, based on achieving a chronic elevation of intraocular pressure (IOP). Methods: A total of 16 animals were used for the glaucoma development model. Rabbits were divided in four groups: Cautery of three vortex veins was performed in the first group (four animals) and cautery of four vortex veins in the second group (four animals). Three vortex veins were ligated in the third group (four animals) and ligation of four vortex veins was performed in the last group (four animals). IOP was measured by Tonovet rebound tonometer during six weeks follow up. The opposite unoperated eye served as control. Results: Cauterization of four vortex veins (second group) and ligation of four vortex veins (fourth group) achieved IOP elevation (40mmHg) but only for the first twenty four hours. The others groups IOP did not reach statistical differences between treated and control eye. None of the methods developed chronic elevation of IOP. Conclusions: Vortex vein surgery in albine rabbits was not able to achieve chronic elevation of IOP. Therefore, none of this methods showed capacity to develop a glaucoma experimental model. 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