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Simplification
Selected AbstractsProgressive Simplification of Tetrahedral Meshes Preserving All Isosurface TopologiesCOMPUTER GRAPHICS FORUM, Issue 3 2003Yi-Jen Chiang In this paper, we propose a novel technique for constructing multiple levels of a tetrahedral volume dataset whilepreserving the topologies of all isosurfaces embedded in the data. Our simplification technique has two majorphases. In the segmentation phase, we segment the volume data into topological-equivalence regions, that is, thesub-volumes within each of which all isosurfaces have the same topology. In the simplification phase, we simplifyeach topological-equivalence region independently, one by one, by collapsing edges from the smallest to the largesterrors (within the user-specified error tolerance, for a given error metrics), and ensure that we do not collapseedges that may cause an isosurface-topology change. We also avoid creating a tetrahedral cell of negative volume(i.e., avoid the fold-over problem). In this way, we guarantee to preserve all isosurface topologies in the entiresimplification process, with a controlled geometric error bound. Our method also involves several additionalnovel ideas, including using the Morse theory and the implicit fully augmented contour tree, identifying typesof edges that are not allowed to be collapsed, and developing efficient techniques to avoid many unnecessary orexpensive checkings, all in an integrated manner. The experiments show that all the resulting isosurfaces preservethe topologies, and have good accuracies in their geometric shapes. Moreover, we obtain nice data-reductionrates, with competitively fast running times. [source] An Adaptive Sampling Scheme for Out-of-Core SimplificationCOMPUTER GRAPHICS FORUM, Issue 2 2002Guangzheng Fei Current out-of-core simplification algorithms can efficiently simplify large models that are too complex to be loaded in to the main memory at one time. However, these algorithms do not preserve surface details well since adaptive sampling, a typical strategy for detail preservation, remains to be an open issue for out-of-core simplification. In this paper, we present an adaptive sampling scheme, called the balanced retriangulation (BR), for out-of-core simplification. A key idea behind BR is that we can use Garland's quadric error matrix to analyze the global distribution of surface details. Based on this analysis, a local retriangulation achieves adaptive sampling by restoring detailed areas with cell split operations while further simplifying smooth areas with edge collapse operations. For a given triangle budget, BR preserves surface details significantly better than uniform sampling algorithms such as uniform clustering. Like uniform clustering, our algorithm has linear running time and small memory requirement. [source] Simplification of separation of the reaction mixture after transesterification of vegetable oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2008Martin Hájek Abstract A heterogeneous reaction mixture is formed by transesterification of vegetable oils. The reaction mixture contains mainly methyl esters of higher fatty acids and glycerol. From this mixture, biodiesel is gained by spontaneous sedimentation in the gravitational field. The sedimentation can be considerably accelerated by controlled addition of water. It was found that addition of small amounts of water to the crude reaction mixture significantly affected the mixture, and substantial changes in the speed of the separation took place. Considerable differences in the composition and quality of the ester and glycerol phases occurred. The optical properties (transmittance and refractive indices) of the heterogeneous reaction mixture are changed after addition of water; this change can be observed spectrophotometrically. This method is applicable to all types of vegetable oils including waste frying oils. [source] Simplification: is it sufficient?HIV MEDICINE, Issue 2000Jonathan D Cartledge First page of article [source] Generation and adaptation of computational surface meshes from discrete anatomical dataINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 6 2004Pascal J. FreyArticle first published online: 27 MAY 200 Abstract Fast and accurate scanning devices are nowadays widely used in many engineering and biomedical fields. The resulting discrete data is usually directly converted into polygonal surface meshes, using ,brute-force' algorithms, often resulting in meshes that may contain several millions of polygons. Simplification is therefore required in order to make storage, computation and display possible if not efficient. In this paper, we present a general scheme for mesh simplification and optimization that allows to control the geometric approximation as well as the element shape and size quality (required for numerical simulations). Several examples ranging from academic to complex biomedical geometries (organs) are presented to illustrate the efficiency and the utility of the proposed approach. Copyright © 2004 John Wiley & Sons, Ltd. [source] Simplification of analytical models and incorporation with CFD for the performance predication of closed-wet cooling towersINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2002Ala Hasan Abstract Simplified analytical models are developed for evaluating the thermal performance of closed-wet cooling towers (CWCTs) for use with chilled ceilings in cooling of buildings. Two methods of simplification are used with regard to the temperature of spray water inside the tower. The results obtained from these models for a prototype cooling tower are very close to experimental measurements. The thermal performance of the cooling tower is evaluated under nominal conditions. The results show that the maximum difference in the calculated cooling water heat or air sensible heat between the two simplified methods and a general computational model is less than 3%. The analytical model distribution of the sensible heat along the tower is then incorporated with computational fluid dynamics (CFD) to assess the thermal performance of the tower. It is found that CFD results agree well with the analytical results when the air flow is simulated with air supply from the bottom of the tower, which represents a uniform air flow. CFD shows the importance of the uniform distribution of air and spray water to achieve optimum design. Copyright © 2002 John Wiley & Sons, Ltd. [source] Reducing racial bias in the penalty phase of capital trialsBEHAVIORAL SCIENCES & THE LAW, Issue 5 2008Netta Shaked-Schroer M.A. Past research (e.g. Lynch & Haney, 2000) has shown that race plays a significant role in juror decision making in the penalty phase of capital murder trials. This study investigates the possibility of reducing juror bias towards Blacks by altering the content of jury instructions. White and non-White participants received trial information and jury instructions in which the defendant's race (Black or White) and the instruction type (standard or simplified) were manipulated. Participants rendered a sentence recommendation, identified factors they considered to be aggravating or mitigating, and responded to instruction comprehension questions. Bias against the Black defendant was significantly reduced when simplified instructions were used and when the defendant was judged by racially diverse jurors. Simplification also led to better comprehension of sentencing instructions. Implications for capital trials are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] "Less is more" and the art of modeling complex phenomena: Simplification may but need not be the key to handle large networksCOMPLEXITY, Issue 2 2005Peter Schuster Editor in Chief of Complexity No abstract is available for this article. [source] An analytical model for steady coextrusion of viscoplastic fluids in thin slit dies with wall slipPOLYMER ENGINEERING & SCIENCE, Issue 4 2010Dilhan M. Kalyon Coextrusion is widely used to fabricate multilayered products with each layer providing a separate functionality, including barrier resistance to gases, strength, and printability. Here an analytical model of the coextrusion die flow of two incompressible, viscoplastic fluids in a slit die, subject to nonlinear wall slip and under fully developed and isothermal conditions, is developed to allow the prediction of the steady-state velocity and shear stress distributions and the flow rate versus pressure gradient relationship. The resulting model is applied to the coextrusion of two layers of viscoplastic fluids in a thin rectangular slit die (slit gap, h , slit width, W). The analytical solution recognizes a number of distinct flow conditions (eleven cases) that need to be treated separately. The solutions for all eleven cases are provided along with an apriori identification methodology for the determination of the applicable case, given the shear viscosity and wall slip parameters of the two viscoplastic fluids, the slit geometry and the flow conditions. Simplifications of the model would provide the solutions for the fully developed and isothermal coextrusion flows of any combination of Hershel-Bulkley, Bingham, power-law and Newtonian fluids with or without wall slip at one or both walls of the slit die. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers [source] Analytical models for the mean flow inside dense canopies on gentle hilly terrainTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 634 2008D. Poggi Abstract Simplifications and scaling arguments employed in analytical models that link topographic variations to mean velocity perturbations within dense canopies are explored using laboratory experiments. Laser Doppler anemometry (LDA) measurements are conducted in a neutrally-stratified boundary-layer flow within a large recirculating flume over a train of gentle hills covered by a dense canopy. The hill and canopy configuration are such that the mean hill slope is small and the hill is narrow in relation to the canopy (H/L , 1 and Lc/L , 1, where H is the hill height, L the half-length, and Lc the canopy adjustment length-scale). The LDA data suggest that the often-criticized linearizations of the advective terms, turbulent-shear-stress gradients and drag force appear reasonable except in the deep layers of the canopy. As predicted by a previous analytical model, the LDA data reveal a recirculation region within the lower canopy on the lee slope. Adjusting the outer-layer pressure perturbations by a virtual ground that accounts for the mean streamline distortions induced by this recirculation zone improves this model's performance. For the velocity perturbations in the deeper layers of the canopy, a new analytical model, which retains a balance between mean horizontal advection, mean pressure gradient and mean drag force but neglects the turbulent-shear-stress gradient, is developed. The proposed model reproduces the LDA measurements better than the earlier analytical model, which neglected advection but retained the turbulent-shear-stress gradient in the lower layers of the canopy and near the hill top. This finding is consistent with the fact that the earlier model was derived for tall hills in which advection inside the canopy remains small. In essence, the newly-proposed model for the narrow hill studied here assumes that in the deeper layers of the canopy the spatial features of the mean flow perturbations around their background state can be approximated by the inviscid mean-momentum equation. We briefly discuss how to integrate all these findings with recent advances in canopy lidar remote-sensing measurements of general topography and canopy height. Copyright © 2008 Royal Meteorological Society [source] HYBRID ACE: COMBINING SEARCH DIRECTIONS FOR HEURISTIC PLANNINGCOMPUTATIONAL INTELLIGENCE, Issue 3 2005Dimitris Vrakas One of the most promising trends in Domain-Independent AI Planning, nowadays, is state-space heuristic planning. The planners of this category construct general but efficient heuristic functions, which are used as a guide to traverse the state space either in a forward or in a backward direction. Although specific problems may favor one or the other direction, there is no clear evidence why any of them should be generally preferred. This paper presents Hybrid-AcE, a domain-independent planning system that combines search in both directions utilizing a complex criterion that monitors the progress of the search, to switch between them. Hybrid AcE embodies two powerful domain-independent heuristic functions extending one of the AcE planning systems. Moreover, the system is equipped with a fact-ordering technique and two methods for problem simplification that limit the search space and guide the algorithm to the most promising states. The bi-directional system has been tested on a variety of problems adopted from the AIPS planning competitions with quite promising results. [source] Combined compression and simplification of dynamic 3D meshesCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 4 2009Libor Vá Abstract We present a new approach to dynamic mesh compression, which combines compression with simplification to achieve improved compression results, a natural support for incremental transmission and level of detail. The algorithm allows fast progressive transmission of dynamic 3D content. Our scheme exploits both temporal and spatial coherency of the input data, and is especially efficient for the case of highly detailed dynamic meshes. The algorithm can be seen as an ultimate extension of the clustering and local coordinate frame (LCF)-based approaches, where each vertex is expressed within its own specific coordinate system. The presented results show that we have achieved better compression efficiency compared to the state of the art methods. Copyright © 2008 John Wiley & Sons, Ltd. [source] Multi-resolution collision handling for cloth-like simulationsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2005Nitin Jain Abstract We present a novel multi-resolution algorithm for simulation of complex cloth-like deforming meshes. Our algorithm precomputes a multi-resolution hierarchy by using a combination of ,chromatic decomposition'1 and polygonal simplification of the underlying mesh. At runtime we selectively refine or coarsen the mesh based on the collision proximity of the mesh primitives with non-adjacent primitives. Our algorithm handles all kind of contacts, including self collisions among mesh primitives. The multi-resolution hierarchy is used to compute simplification of contact manifolds and to accelerate collision detection and response computations. We have implemented our algorithm on a high-end PC and applied it to complex simulations with tens of thousands of polygons. In practice, our algorithm is able to achieve interactive performance, while maintaining good visual fidelity. Copyright © 2005 John Wiley & Sons, Ltd. [source] Progressive Hulls for Intersection ApplicationsCOMPUTER GRAPHICS FORUM, Issue 2 2003Nikos Platis Abstract Progressive meshes are an established tool for triangle mesh simplification. By suitably adapting the simplification process, progressive hulls can be generated which enclose the original mesh in gradually simpler, nested meshes. We couple progressive hulls with a selective refinement framework and use them in applications involving intersection queries on the mesh. We demonstrate that selectively refinable progressive hulls considerably speed up intersection queries by efficiently locating intersection points on the mesh. Concerning the progressive hull construction, we propose a new formula for assigning edge collapse priorities that significantly accelerates the simplification process, and enhance the existing algorithm with several conditions aimed at producing higher quality hulls. Using progressive hulls has the added advantage that they can be used instead of the enclosed object when a lower resolution of display can be tolerated, thus speeding up the rendering process. ACM CSS: I.3.3 Computer Graphics,Picture/Image Generation, I.3.5 Computer Graphics,Computational Geometry and Object Modeling, I.3.7 Computer Graphics,Three-Dimensional Graphics and Realism [source] An Adaptive Sampling Scheme for Out-of-Core SimplificationCOMPUTER GRAPHICS FORUM, Issue 2 2002Guangzheng Fei Current out-of-core simplification algorithms can efficiently simplify large models that are too complex to be loaded in to the main memory at one time. However, these algorithms do not preserve surface details well since adaptive sampling, a typical strategy for detail preservation, remains to be an open issue for out-of-core simplification. In this paper, we present an adaptive sampling scheme, called the balanced retriangulation (BR), for out-of-core simplification. A key idea behind BR is that we can use Garland's quadric error matrix to analyze the global distribution of surface details. Based on this analysis, a local retriangulation achieves adaptive sampling by restoring detailed areas with cell split operations while further simplifying smooth areas with edge collapse operations. For a given triangle budget, BR preserves surface details significantly better than uniform sampling algorithms such as uniform clustering. Like uniform clustering, our algorithm has linear running time and small memory requirement. [source] A Multiresolution Model for Soft Objects Supporting Interactive Cuts and LacerationsCOMPUTER GRAPHICS FORUM, Issue 3 2000Fabio Ganovelli Performing a really interactive and physically-based simulation of complex soft objects is still an open problem in computer animation/simulation. Given the application domain of virtual surgery training, a complete model should be quite realistic, interactive and should enable the user to modify the topology of the objects. Recent papers propose the adoption of multiresolution techniques to optimize time performance by representing at high resolution only the object parts considered more important or critical. The speed up obtainable at simulation time are counterbalanced by the need of a preprocessing phase strongly dependent on the topology of the object, with the drawback that performing dynamic topology modification becomes a prohibitive issue. In this paper we present an approach that couples multiresolution and topological modifications, based on the adoption of a particle systems approach to the physical simulation. Our approach is based on a tetrahedral decomposition of the space, chosen both for its suitability to support a particle system and for the ready availability of many techniques recently proposed for the simplification and multiresolution management of 3D simplicial decompositions. The multiresolution simulation system is designed to ensure the required speedup and to support dynamic changes of the topology, e.g. due to cuts or lacerations of the represented tissue. [source] Some Learning Methods in Functional NetworksCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2000Enrique Castillo This article is devoted to learning functional networks. After a short introduction and motivation of functional networks using a CAD problem, four steps used in learning functional networks are described: (1) selection of the initial topology of the network, which is derived from the physical properties of the problem being modeled, (2) simplification of this topology, using functional equations, (3) estimation of the parameters or weights, using least squares and minimax methods, and (4) selection of the subset of basic functions leading to the best fit to the available data, using the minimum-description-length principle. Several examples are presented to illustrate the learning procedure, including the use of a separable functional network to recover the missing data of the significant wave height records in two different locations, based on a complete record from a third location where the record is complete. [source] Extended Mechanical Circulatory Support With a Continuous-Flow Rotary Left Ventricular Assist DeviceCONGESTIVE HEART FAILURE, Issue 2 2010Scott Harris DO Background LVAD therapy is an established treatment modality for patients with advanced heart failure. Pulsatile LVADs have limitations in design precluding their use for extended support. Continuous-flow rotary LVADs represent an innovative design with potential for small size and greater reliability by simplification of the pumping mechanism. Methods In a prospective multicenter study, 281 patients urgently listed (United Network for Organ Sharing status 1A or 1B) for heart transplant underwent implant of a continuous-flow LVAD. Survival and transplant rates were assessed at 18 months. Patients were assessed for adverse events throughout the study and for quality of life, functional status, and organ function for 6 months. Results Of 281 patients, 222 (79%) underwent transplant or LVAD removal for cardiac recovery or had ongoing LVAD support at 18-month follow-up. Actuarial survival on support was 72% (95% confidence interval, 65%,79%) at 18 months. At 6 months, there were significant improvements in functional status and 6-minute walk test results (from 0% to 83% of patients in New York Heart Association functional class I or II and from 13% to 89% of patients completing a 6-minute walk test) and in quality of life (mean values improved 41% with Minnesota Living With Heart Failure and 75% with Kansas City Cardiomyopathy questionnaires). Major adverse events included bleeding, stroke, right heart failure, and percutaneous lead infection. Pump thrombosis occurred in 4 patients. Conclusions A continuous-flow LVAD provides effective hemodynamic support for at least 18 months in patients awaiting transplant, with improved functional status and quality of life. [source] Shared Services Transformation: Conceptualization and Valuation from the Perspective of Real OptionsDECISION SCIENCES, Issue 3 2009Ning Su ABSTRACT In today's volatile global economy, where many organizations face severe pressure to downsize, the "shared services" model, in which a firm merges common functions performed by multiple units into a single service delivery organization, provides an innovative approach to make business more efficient and effective. To successfully implement shared services, firms need to strategically decide whether and how to pursue various service transformation alternatives such as simplification, standardization, consolidation, insourcing, or outsourcing. In this study, we develop the notion of real options into a unique theoretical lens for conceptualizing service organizations and their transformation in an uncertain business environment. Specifically, we view service organization as a set of strategic options that give the firm preferential access to future transformation opportunities. We create a taxonomy of these options, and introduce a decision methodology for valuing alternative shared services transformation approaches. We illustrate this methodology by applying it in a real business case to justify a global firm's decision regarding the transformation of its finance organization. [source] Panic disorder: a review of DSM-IV panic disorder and proposals for DSM-V,DEPRESSION AND ANXIETY, Issue 2 2010Michelle G. Craske Ph.D Abstract This review covers the literature since the publication of DSM-IV on the diagnostic criteria for panic attacks (PAs) and panic disorder (PD). Specific recommendations are made based on the evidence available. In particular, slight changes are proposed for the wording of the diagnostic criteria for PAs to ease the differentiation between panic and surrounding anxiety; simplification and clarification of the operationalization of types of PAs (expected vs. unexpected) is proposed; and consideration is given to the value of PAs as a specifier for all DSM diagnoses and to the cultural validity of certain symptom profiles. In addition, slight changes are proposed for the wording of the diagnostic criteria to increase clarity and parsimony of the criteria. Finally, based on the available evidence, no changes are proposed with regard to the developmental expression of PAs or PD. This review presents a number of options and preliminary recommendations to be considered for DSM-V. Depression and Anxiety, 2010. © 2010 Wiley-Liss, Inc. [source] The ,New Minimalist Approach' to Private-Sector Development: A Critical AssessmentDEVELOPMENT POLICY REVIEW, Issue 4 2006Tilman Altenburg Recent literature on private-sector development emphasises the need to establish a ,level playing field' and tends to disregard selective supportive interventions. The most commonly highlighted elements are administrative simplification and effective property rights policies, with business services largely left to private providers - what we call the ,new minimalist approach' (NMA). However, the NMA is based on certain unrealistic assumptions and is barely backed by empirical evidence. A range of complementary public policies is needed to create competitive sectors and overcome internal constraints, especially in small-scale economies. [source] Accelerated nervous system development contributes to behavioral efficiency in the laboratory mouse: A behavioral review and theoretical proposalDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2001Ian Q. Whishaw Abstract The emergence of the laboratory mouse as a favored species for genetic research has posed a number of problems for scientists interested in the reflection of genetic influences in mouse behavior. It is commonly thought that rat behavior, which has been studied more extensively than mouse behavior, could be easily generalized to mice. In this article, a number of categories of behavior displayed by the mouse (motor, spatial, defensive, social) are reviewed and contrasted with the same categories of behavior displayed by the rat. The comparison suggests that mouse behavior is simpler and more dependent upon elementary actions than the behavior of the rat. We suggest that the behavioral simplification in the mouse adapts it for a different ecological niche than that occupied by the rat. We propose that this simplification may be mediated by accelerated brain maturation during development. We further propose that this developmental acceleration in the mouse renders it less dependent upon complex social behavior and plastic nervous system changes associated with learning than the rat. This difference poses problems for the development of relevant methods of behavioral analysis and interpretation. Since the mouse's biological adaptations will be reflected in laboratory behavior, suggestions are made for behavioral approaches to the study and interpretation of mouse behavior. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 39: 151,170, 2001 [source] Relationship between mean blood glucose and glycated haemoglobin in Type 2 diabetic patientsDIABETIC MEDICINE, Issue 2 2008K. Makris Abstract Aims To correlate the values of MBG to HbA1c in Greek patients with Type 2 diabetes and/or metabolic syndrome. Methods We followed up 140 Greek adult patients: 92 patients with Type 2 diabetes treated with insulin or oral glucose-lowering medication, and 48 patients with newly diagnosed Type 2 diabetes or metabolic syndrome not receiving any treatment. MBG was calculated for each patient from self-measurements of blood glucose using a portable glucometer, made six times a day (before eating and 2 h after a meal), three times a week for 1 month. HbA1c was determined by HPLC at 0 and 12 weeks. Results, HbA1c at 0 (x) and 12 weeks (y) correlated strongly (y = 0.790x + 1.115, r = 0.92), confirming that the patient's glycaemic status remained stable during the whole period of follow-up. Linear regression was performed on MBG values; HbA1c at 12 weeks, sex, age, body mass index (BMI) and patient status (Type 2 diabetes treated or not) were used as independent variables. None of the independent variables reached statistical significance in the model, with the exception of HbA1c at 12 weeks. The final model was: MBG (mg/dl) = (34.74 × HbA1c) , 79.21, r = 0.93; or MBG (mmol/l) = 1.91 × HbA1c , 4.36, r = 0.93. Conclusions Our results establish for the first time a strong correlation between MBG and HbA1c in Type 2 diabetic patients and support the idea of expressing HbA1c results as MBG. This will help patients to gain a clearer interpretation of the result, with less confusion. This simplification will allow every person with diabetes using home glucose-monitoring to understand his or her own target level. [source] EMPLOYMENT TAXES: WHERE ARE WE GOING?ECONOMIC AFFAIRS, Issue 1 2003John Whiting Employment taxes have become more complicated over time, and too much of an administrative burden is now placed on employers, especially smaller ones. Combining PAYE and NIC has the potential for big simplification of the system. My basic thesis is that circumstances have changed dramatically, and so must the system, because all is not well in the employment taxes area. [source] After the Health Check What is the Future for the Common Agricultural Policy?EUROCHOICES, Issue 1 2009Nach dem Gesundheitscheck: Wie geht es weiter mit der Gemeinsamen Agrarpolitik? Summary After the Health Check What is the Future for the Common Agricultural Policy? The CAP has now completed another stage in its development. The Health Check negotiating marathon has ended. The Czech Republic has been against unequal conditions for member states as these deform fair competition and the common market. Progressive modulation in the originally proposed form would have created barriers to a unified Europe, thus going against the motto of the Czech presidency ,Europe without Barriers'. The Czech Republic can certainly be satisfied with the essence of the compromise. The cancellation of the milk quota in 2015 is a liberalising measure, and as such we support it. The Health Check opens the door to the Czech presidency for a discussion on the elimination of unfair differences in direct payments between member states and we will definitely take up the opportunity. After 2013 the CAP will have to take much greater account of the situation following the unprecedented expansion of the EU in 2004 and 2006. For the Czech Republic, a further reinforcing of freedom in decision making for farmers and their focus on the specific needs of the local, community and global market is fundamental. Further simplification of the CAP and ,better regulation', focussing on a reduction in the administrative burden on farmers, is one of the priority challenges. La PAC a maintenant atteint un autre stade de son développement. Le marathon de négociation du bilan de santé a abouti. La République tchèque s'est opposée aux conditions inégales proposées aux pays membres car elles faussent la concurrence équitable et le marché commun. La modulation progressive sous sa forme initiale aurait créé des barrières dans une Europe unifiée, ce qui va à l'encontre de la devise de la présidence tchèque "Une Europe sans barrières". La République tchèque peut certainement être satisfaite de l'essence du compromis. La suppression du système des quotas laitiers en 2015 est une mesure de libéralisation et nous la soutenons en tant que telle. Le bilan de santé ouvre la porte à la présidence tchèque pour une discussion sur l'élimination des différences injustes entre paiements directs selon le pays membre et nous profiterons bien entendu de l'occasion. Après 2013, la PAC devra prendre davantage en compte la situation créée par l'élargissement sans précédent de l'UE entre 2004 et 2006. Pour la République tchèque, il est fondamental de renforcer encore la liberté qu'ont les agriculteurs pour prendre leurs décisions et de s'orienter vers les besoins spécifiques du marché local, communautaire et mondial. Un des défis prioritaires est de continuer à simplifier la PAC et d'améliorer la réglementation en s'orientant vers une réduction de la charge administrative qui pèse sur les agriculteurs. Eine weitere Phase in der Entwicklung der Gemeinsamen Agrarpolitik ist nun abgeschlossen. Der Verhandlungsmarathon hinsichtlich des Gesundheitschecks ist vorbei. Die Tschechische Republik war dagegen, dass für die Mitgliedsstaaten unterschiedliche Bedingungen gelten sollen, da diese den fairen Wettbewerb und den gemeinsamen Markt verzerren. Eine progressive Modulation in der ursprünglich vorgeschlagenen Form hätte einem einheitlichen Europa Steine in den Weg gelegt und somit dem Motto "Europa ohne Grenzen" der tschechischen Präsidentschaft widersprochen. Die Tschechische Republik hat zweifellos mit dem Kompromiss ein im Wesentlichen zufriedenstellendes Ergebnis erzielt. Die Abschaffung der Milchquote bis 2015 ist eine Maßnahme zur Liberalisierung, und als solche findet sie unsere Unterstützung. Der Gesundheitscheck eröffnet der tschechischen Präsidentschaft die Diskussion über die Beseitigung unterschiedlich hoher , und somit ungerechter , Direktzahlungen an die Mitgliedsstaaten. Diese Gelegenheit werden wir uns nicht entgehen lassen. Nach 2013 wird sich die GAP sehr viel mehr mit der Situation beschäftigen müssen, die sich aus der beispiellosen EU-Erweiterung aus den Jahren 2004 und 2006 ergibt. Für die Tschechische Republik ist es von grundlegender Bedeutung, die Entscheidungsfreiheit für Landwirte und deren Orientierung an den lokalen, regionalen und globalen Märkten fortwährend zu stärken. Die weitere Vereinfachung der GAP und eine "bessere Regulierung", die den Verwaltungsaufwand für Landwirte verringern soll, gehören zu den vorrangigen Zielen. [source] Fine-Tuning Ligands for Catalysis Using Supramolecular StrategiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29 2007Vincent F. Slagt Abstract Coordinative bonds have been used to prepare supramolecular ligands leading to well-defined catalysts formed by assembly. The construction of these ligands is based on selective metal,ligand interactions between nitrogen donor atoms of phosphorus-nitrogen building blocks and various zinc(II) porphyrins. The major advantage of this supramolecular approach of catalyst preparation is the simplification of ligand variation enabling straightforward modification of steric, electronic and chiral properties of the supramolecular ligand. A large number of new ligands becomes accessible by this modular variation of the building blocks. The ligand assembly based on pyridyl phosphites and zinc(II) porphyrin with electron-withdrawing substituents led to a twelve-fold increase in activity and an increase in enantioselectivity from 17 to 50,% in the rhodium-catalyzed hydrogenation of dimethyl itaconate. The first examples of assemblies based on non-chiral ligands and chiral zinc(II) porphyrin template molecules show, as proof of principle, an enantiomeric excess up to 18,% in the asymmetric palladium-catalyzed allylic alkylation. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Control of eye orientation: where does the brain's role end and the muscle's begin?EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2004Dora E. Angelaki Abstract Our understanding of how the brain controls eye movements has benefited enormously from the comparison of neuronal activity with eye movements and the quantification of these relationships with mathematical models. Although these early studies focused on horizontal and vertical eye movements, recent behavioural and modelling studies have illustrated the importance, but also the complexity, of extending previous conclusions to the problems of controlling eye and head orientation in three dimensions (3-D). An important facet in understanding 3-D eye orientation and movement has been the discovery of mobile, soft-tissue sheaths or ,pulleys' in the orbit which might influence the pulling direction of extraocular muscles. Appropriately placed pulleys could generate the eye-position-dependent tilt of the ocular rotation axes which are characteristic for eye movements which follow Listing's law. Based on such pulley models of the oculomotor plant it has recently been proposed that a simple two-dimensional (2-D) neural controller would be sufficient to generate correct 3-D eye orientation and movement. In contrast to this apparent simplification in oculomotor control, multiple behavioural observations suggest that the visuo-motor transformations, as well as the premotor circuitry for saccades, pursuit eye movements and the vestibulo-ocular reflexes, must include a neural controller which operates in 3-D, even when considering an eye plant with pulleys. This review summarizes the most recent work and ideas on this controversy. In addition, by proposing directly testable hypotheses, we point out that, in analogy to the previously successful steps towards elucidating the neural control of horizontal eye movements, we need a quantitative characterization first of motoneuron and next of premotor neuron properties in 3-D before we can succeed in gaining further insight into the neural control of 3-D motor behaviours. [source] Efficient reduction of fault current through the grounding grid of a substation supplied by an overhead lineEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 3 2006Ljubivoje M. Popovi Abstract The paper presents a directly applicable and reasonably accurate method for the evaluation of the effects of the counterpoise, the measure for the reduction of the fault current through the substation grounding grid. Under practical conditions the magnitude of the current diverted from a substation grounding grid by the counterpoise conductor is a very complex function of the self and mutual impedances of overhead and underground conductors, substation grounding impedance, transmission line towers resistance, proximity effect between the grounding grid and the counterpoise conductor, as well as on many other factors of lower order. Therefore certain idealizations and simplification of the real physical model were indispensable to develop the mathematical model presented here. The obtained expressions are mostly based on the general equations of a line represented by its lumped parameters and the general equations of uniform ladder circuits. Copyright © 2006 John Wiley & Sons, Ltd. [source] Design syntheses and mitochondrial complex I inhibitory activity of novel acetogenin mimicsFEBS JOURNAL, Issue 9 2000Kaoru Kuwabara Some natural acetogenins are the most potent inhibitors of mitochondrial complex I. These compounds are characterized by two functional units [i.e. hydroxylated tetrahydrofuran (THF) and ,,,-unsaturated ,-lactone ring moieties] separated by a long alkyl spacer. To elucidate which structural factors of acetogenins, including their active conformation, are crucial for the potent inhibitory activity we synthesized a novel bis-acetogenin and its analogues possessing two ,-lactone rings connected to bis-THF rings by flexible alkyl spacers. The inhibitory potency of the bis-acetogenin with bovine heart mitochondrial complex I was identical to that of bullatacin, one of the most potent natural acetogenins. This result indicated that one molecule of the bis-acetogenin does not work as two reactive inhibitors, suggesting that a ,-lactone and the THF ring moieties act in a cooperative manner on the enzyme. In support of this, either of the two ring moieties synthesized individually showed no or very weak inhibitory effects. Moreover, combined use of the two ring moieties at various molar ratios exhibited no synergistic enhancement of the inhibitory potency. These observations indicate that both functional units work efficiently only when they are directly linked by a flexible alkyl spacer. Therefore, some specific conformation of the spacer must be important for optimal positioning of the two units in the enzyme. Furthermore, the ,,,-unsaturated ,-lactone, the 4-OH group in the spacer region, the long alkyl tail attached to the THF unit and the stereochemistry surrounding the hydroxylated bis-THF rings were not crucial for the activity, although these are the most common structural features of natural acetogenins. The present study provided useful guiding principles not only for simplification of complicated acetogenin structure, but also for further wide structural modifications of these molecules. [source] Simplicity versus Fairness in Means Testing: The Case of Civil Legal AidFISCAL STUDIES, Issue 4 2003Alexy Buck Abstract For most state financial benefits, the making of any payment, or its level, depends upon a means test to assess the applicant's income or wealth. Attempts to make such tests fair often lead to procedures that are complicated to administer and confusing for the applicant. This paper describes the analysis underlying a review of means testing for civil legal aid in England and Wales, to achieve considerable simplification without sacrificing fairness. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||