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Selected AbstractsAn amphioxus winged helix/forkhead gene, AmphiFoxD: Insights into vertebrate neural crest evolutionDEVELOPMENTAL DYNAMICS, Issue 3 2002Jr-Kai Yu Abstract During amphioxus development, the neural plate is bordered by cells expressing many genes with homologs involved in vertebrate neural crest induction. However, these amphioxus cells evidently lack additional genetic programs for the cell delaminations, migrations, and differentiations characterizing definitive vertebrate neural crest. We characterize an amphioxus winged helix/forkhead gene (AmphiFoxD) closely related to vertebrate FoxD genes. Phylogenetic analysis indicates that the AmphiFoxD is basal to vertebrate FoxD1, FoxD2, FoxD3, FoxD4, and FoxD5. One of these vertebrate genes (FoxD3) consistently marks neural crest during development. Early in amphioxus development, AmphiFoxD is expressed medially in the anterior neural plate as well as in axial (notochordal) and paraxial mesoderm; later, the gene is expressed in the somites, notochord, cerebral vesicle (diencephalon), and hindgut endoderm. However, there is never any expression in cells bordering the neural plate. We speculate that an AmphiFoxD homolog in the common ancestor of amphioxus and vertebrates was involved in histogenic processes in the mesoderm (evagination and delamination of the somites and notochord); then, in the early vertebrates, descendant paralogs of this gene began functioning in the presumptive neural crest bordering the neural plate to help make possible the delaminations and cell migrations that characterize definitive vertebrate neural crest. © 2002 Wiley-Liss, Inc. [source] Rigid body dynamics in terms of quaternions: Hamiltonian formulation and conserving numerical integrationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2009Peter Betsch Abstract In the present paper unit quaternions are used to describe the rotational motion of a rigid body. The unit-length constraint is enforced explicitly by means of an algebraic constraint. Correspondingly, the equations of motion assume the form of differential-algebraic equations (DAEs). A new route to the derivation of the mass matrix associated with the quaternion formulation is presented. In contrast to previous works, the newly proposed approach yields a non-singular mass matrix. Consequently, the passage to the Hamiltonian framework is made possible without the need to introduce undetermined inertia terms. The Hamiltonian form of the DAEs along with the notion of a discrete derivative make possible the design of a new quaternion-based energy,momentum scheme. Two numerical examples demonstrate the performance of the newly developed method. In this connection, comparison is made with a quaternion-based variational integrator, a director-based energy,momentum scheme, and a momentum conserving scheme relying on the discretization of the classical Euler's equations. Copyright © 2009 John Wiley & Sons, Ltd. [source] An affordable modular mobile robotic platform with fuzzy logic control and evolutionary artificial neural networksJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 8 2004Maurice Tedder Autonomous robotics projects encompass the rich nature of integrated systems that includes mechanical, electrical, and computational software components. The availability of smaller and cheaper hardware components has helped make possible a new dimension in operational autonomy. This paper describes a mobile robotic platform consisting of several integrated modules including a laptop computer that serves as the main control module, microcontroller-based motion control module, a vision processing module, a sensor interface module, and a navigation module. The laptop computer module contains the main software development environment with a user interface to access and control all other modules. Programming language independence is achieved by using standard input/output computer interfaces including RS-232 serial port, USB, networking, audio input and output, and parallel port devices. However, with the same hardware technology available to all, the distinguishing factor in most cases for intelligent systems becomes the software design. The software for autonomous robots must intelligently control the hardware so that it functions in unstructured, dynamic, and uncertain environments while maintaining an autonomous adaptability. This paper describes how we introduced fuzzy logic control to one robot platform in order to solve the 2003 Intelligent Ground Vehicle Competition (IGVC) Autonomous Challenge problem. This paper also describes the introduction of hybrid software design that utilizes Fuzzy Evolutionary Artificial Neural Network techniques. In this design, rather than using a control program that is directly coded, the robot's artificial neural net is first trained with a training data set using evolutionary optimization techniques to adjust weight values between neurons. The trained neural network with a weight average defuzzification method was able to make correct decisions to unseen vision patterns for the IGVC Autonomous Challenge. A comparison of the Lawrence Technological University robot designs and the design of the other competing schools shows that our platforms were the most affordable robot systems to use as tools for computer science and engineering education. © 2004 Wiley Periodicals, Inc. [source] Lessons learned by participants of distributed software developmentKNOWLEDGE AND PROCESS MANAGEMENT: THE JOURNAL OF CORPORATE TRANSFORMATION, Issue 2 2005Seija Komi-Sirviö The maturation of the technical infrastructure has enabled the emergence and growth of distributed software development. This has created tempting opportunities for companies to distribute their software development, for example, to economically favourable countries so as to gain needed expertise or to get closer to customers. Nonetheless, such distribution potentially creates problems that need to be understood and addressed in order to make possible the gains offered. To clarify and understand the most difficult problems and their nature, a survey of individuals engaged in distributed software development was conducted. The purpose of this survey was to gather and share lessons learned in order to better understand the nature of the software development process when operating in a distributed software development environment and the problems that may be associated with such distributed processes. Through a clear appreciation of the risks associated with distributed development it becomes possible to develop approaches for the mitigation of these risks. This paper presents the results of the survey, focusing on the most serious problems raised by the respondents. Some practical guidelines that have been developed by industry to overcome these problems are also briefly summarized. Copyright © 2005 John Wiley & Sons, Ltd. [source] Swallowing Disorders in the Elderly ,THE LARYNGOSCOPE, Issue 4 2002Joshua S. Schindler MD Abstract Changes that occur as a natural part of senescence in the complex action of deglutition predispose us to dysphagia and aspiration. As the "baby-boomers" begin to age, the onset of swallowing difficulties will begin to manifest in a greater number of our population. Recent advances in the evaluation of normal and abnormal swallowing make possible more precise anatomical and physiological diagnoses. Coupled with an understanding of swallowing physiology, such detailed evaluation allows greater opportunity to safely manage dysphagia with directed therapy and appropriate surgical intervention. The current study is a discussion of the changes that occur in deglutition with normal aging, contemporary evaluation of swallowing function, and some of the common causes of dysphagia in elderly patients. [source] Public Spaces for National Commemoration: The Case of Emlotheni Memorial, Port ElizabethANTHROPOLOGY & HUMANISM, Issue 1 2003Birthe Rytter Hansen This article examines how commemorative projects try to deal with the past in the present in order to make possible the imagination of a united South African nation. It looks at how one commemorative site, Emlotheni Memorial, was intended to act as part of the larger nation-building project in South Africa. Taking up issues of ancestral belief, social space, and recognition, this article examines how residents experienced the memorial as exclusive rather than inclusive. The article argues that the memorial site, rather than providing an opportunity for local residents and other South Africans to participate in building a shared history and identity, instead ended up reproducing the segregated past of South Africa. [source] HS09 REPLANTATION SURGERY , THE RECONSTRUCTIVE APPROACHANZ JOURNAL OF SURGERY, Issue 2007L. C. Teoh The function of the replanted parts can be improved if attention to reconstruction techniques is carried out. These reconstructive techniques are: 1) adequate debridement and shortening, 2) stable skeletal fixation, 3) strengthened tendon repairs, 4) quality nerve repair, 5) extensive vascular anastomosis, 6) complete skin coverable, and 7) Early intensive active rehabilitation. 1) The debridement should be generous and the shortening judicious. More than 50% of the skin should be in direct contact, and direct anastomosis of some of vessels should be possible. 2) The skeletal stabilization should be of good very quality that will allow free mobilization of the joints. 3) The repair of the tendons should take advantage of the excess length for a strengthen repair. Some degree of active mobilization should be make possible. 4) Primary nerve grafting or nerve transfer should be considered if there is loss of nerve length. 5) Vascular repair should be on the basis of as many as possible the number of arteries and veins that can be found for anastomosis. 6) Any residual skin defect should be planned for a proper resurfacing within the next 5 to 10 days. 7) Early intensive active rehabilitation should be prescribed. Gradual active ROM for tendon gliding should be instituted with in the first week. The function of the replanted digit and hand has continued to improve with the reconstructive approach. With further experience the reconstructive approach can be done in all cases with confidence. [source] Flow-Based Automatic Generation of Hybrid Picture MazesCOMPUTER GRAPHICS FORUM, Issue 7 2009Fernando J. Wong Abstract A method for automatically generating a picture maze from two different images is introduced throughout this paper. The process begins with the extraction of salient contours and edge tangent flow information from the primary image in order to build the overall maze. Thus, mazes with passages flowing in the main edge directions and walls that effectively represent an abstract version of the primary image can be successfully created. Furthermore, our proposed approach makes possible the use of their solution path as a means of illustrating the main features of the secondary image, while attempting to keep its image motif concealed until the maze has been finally solved. The contour features and intensity of the secondary image are also incorporated into our method in order to determine the areas of the maze to be shaded by allowing the solution path to go through them. Moreover, an experiment has been conducted to confirm that solution paths can be successfully hidden from the participants in the mazes generated using our method. [source] P28 Interleukin-8 from keratinocytes can be used to test for contact allergyCONTACT DERMATITIS, Issue 3 2004Bolli Bjarnason Objective:, To investigate whether secretion of interleukin-8 (IL-8) proteins by keratinocytes following in vitro exposure to a contact allergen can be used to detect contact allergy. Methods:, Suction blisters were made on skin of allergic and anergic subjects to urushiol, the contact allergen of poison ivy. Keratinocyte cultures were prepared and exposed to the allergen in vitro. Controls were the allergen solvent. Variable allergen concentrations, allergen exposure times and cell culture times were used. At the end of each culture time, IL-8 RNA and protein of the culture supernatants were analyzed by PCR and ELISA. Results:, The concentration of IL-8 in the supernatants proved to be a successful way to distinguish between subjects who patch tested positive with a non-toxic concentration of urushiol and subjects who tested negative. In the allergic subjects, a correlation was established between the dose of the allergen and the IL-8 protein concentration in the supernatants. Conclusions:, In vitro testing of contact allergies in patients makes possible an objective assessment of their allergic status without causing a booster effect or risking active sensitizations. The results indicate that the method may be used as an alternative method to animal models for testing consumer products before their marketing, thus avoiding ethical problems and problems related to interpretation of tests because of biological differences between animals and humans. [source] A strategy for efficient handling of fresh tumor needle biopsies that allows histological and cytopathological assessmentDIAGNOSTIC CYTOPATHOLOGY, Issue 5 2008C.C.P.M., Marta C. Cohen M.D. Abstract Neo-adjuvant chemotherapy prior to surgery is used in the management of many pediatric solid tumors, and diagnosis is therefore valuable and is frequently made by percutaneous needle biopsy. We describe a method that enhances tissue preservation and obtains a sample for rapid cytopathological assessment. Biopsies are placed in Ham's F10 culture's medium in theatre and transferred to pathology. The biopsies are retrieved from the medium and dealt as before (submit to cytogenetics; fix in glutharaldheyde; snap frozen at ,80°C and routine histology). An equal amount of 90% alcohol is then added to the Ham culture's medium fluid received from theatre before performing a cytospin preparation and a cell clot. We used this method in the diagnosis of 16 tumors demonstrating that this allows a more efficient handling of the biopsy, makes possible a same day diagnosis, enhances the quality of the immunohistochemistry and maximizes the amount of tissue available for diagnosis. Diagn. Cytopathol. 2008;36:285,289. © 2008 Wiley-Liss, Inc. [source] Towards a Field OntologyDIALECTICA, Issue 1 2006Christina Schneider The aim of the present article is to make the notion of an ontology of fields mathematically rigorous. The conclusion will be that couching an ontology in terms of mathematical bundles and cross-sections (i.e. fields) both (1) captures many important intuitions of conventional ontologies, including the universal-particular paradigm, the connection of universals and their ,instantiations', and the notion of ,possibility', and (2) makes possible the framing of ontologies without ,substrata', bare particulars, and primitive particularizers (a goal that trope ontologies, for example, have sought to attain). [source] Proteomic Identification of the Involvement of the Mitochondrial Rieske Protein in EpilepsyEPILEPSIA, Issue 3 2005Heike Junker Summary:,Purpose: Kindled seizures are widely used to model epileptogenesis, but the molecular mechanisms underlying the attainment of kindling status are largely unknown. Recently we showed that achievement of kindling status in the Sprague,Dawley rat is associated with a critical developmental interval of 25 ± 1 days; the identification of this long, well-defined developmental interval for inducing kindling status makes possible a dissection of the cellular and genetic events underlying this phenomenon and its relation to normal and pathologic brain function. Methods: By using proteomics on cerebral tissue from our new rat kindling model, we undertook a global analysis of protein expression in kindled animals. Some of the identified proteins were further investigated by using immunohistochemistry. Results: We report the identification of a modified variant of the Rieske iron-sulfur protein, a component of the mitochondrial cytochrome bc1 complex, whose isoelectric point is shifted toward more alkaline values in the hippocampus of kindled rats. By immunohistochemistry, the Rieske protein is well expressed in the hippocampus, except in the CA1 subfield, an area of selective vulnerability to seizures in humans and animal models. We also noted an asymmetric, selective expression of the Rieske protein in the subgranular neurons of the dorsal dentate gyrus, a region implicated in neurogenesis. Conclusions: These results indicate that the Rieske protein may play a role in the response of neurons to seizure activity and could give important new insights into the molecular pathogenesis of epilepsy. [source] Determining soil saturated hydraulic conductivity and sorptivity from single ring infiltration testsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2007J. Touma Summary The difference between the cumulative infiltration occurring during three-dimensional axisymmetric and one-dimensional vertical flow is a linear function of time. The slope of this line is a function of the source radius, initial and final volumetric soil water contents and the soil sorptivity. This allows the determination of the sorptivity and saturated conductivity of the soil from data of axisymmetric flow in a single ring of small diameter under negligible head of water. The method is based on the optimization of the sorptivity and saturated conductivity on the one-dimensional vertical cumulative infiltration inferred from axisymmetric flow data. To examine the reliability of the method to determine these parameters, numerical three- and one-dimensional data are generated on soils with known hydrologic properties from the literature. The linearity versus time of the difference of the two types of flow is verified. Several physically based expressions for the vertical cumulative infiltration as a function of time are considered. The optimized values of the sorptivity and saturated conductivity are compared to the their real known values. Despite the large errors on the optimized parameters, namely the saturated conductivity, the error on the vertical predicted cumulative infiltration is limited to 10%. This makes possible the application of this method on a large scale for hydrological modelling purposes. [source] MANAGING PLACE AND IDENTITY: THE MARIN COAST MIWOK EXPERIENCEGEOGRAPHICAL REVIEW, Issue 1 2002JENNIFER SOKOLOVE ABSTRACT. Group identity serves as a mechanism for claiming rights of control and access to land in the United States. Public land managers face myriad identity-based claims to land in their care. Identity shapes claims that must appear valid within the strictures of a legal system created by a dominant culture to serve its interests. The very form of those systems,of which public lands are a large part,makes possible the expression of particular forms of identity. The story of the Coast Miwok community and the Point Reyes National Seashore suggests that geographical links among identity, landscape, and history are actively constructed through political work and rarely are as obvious as they first appear. Both the formal legal process of federal tribal recognition and restoration and the far less formal Coast Miwok claims to land at Point Reyes National Seashore teach important lessons about neotraditional identity-based claims to public land. [source] Magnetic-Field-Induced Phase-Selective Synthesis of Ferrosulfide Microrods by a Hydrothermal Process: Microstructure Control and Magnetic Properties,ADVANCED FUNCTIONAL MATERIALS, Issue 8 2006Z. He Abstract Microrods of the ferrosulfide minerals greigite (Fe3S4) and marcasite (FeS2) are selectively synthesized by an in,situ magnetic-field-assisted hydrothermal route. Each complex microrod is composed of fine building blocks with different shapes. The unique magnetic properties of the microrods and electrical performance of a single microrod are studied. The results demonstrate that the magnetic properties of the ferrosulfide minerals are strongly related to their corresponding microstructures. The value of the low-temperature transition increases as the greigite component in the product decreases. The combination of small-molecule sulfur precursors and an applied magnetic field makes possible the selective synthesis of ferrosulfide minerals with different phases and distinct microstructures, underlining the fact that the magnetic field can be a useful tool as well as an independent parameter for the phase-selective synthesis and self-assembly of inorganic building blocks in solution chemistry. [source] Flying vaccinator; a transgenic mosquito delivers a Leishmania vaccine via blood feedingINSECT MOLECULAR BIOLOGY, Issue 3 2010D. S. Yamamoto Abstract ,Flying vaccinator' is the concept of using genetically engineered hematophagous insects to deliver vaccines. Here we show the generation of a transgenic anopheline mosquito that expresses the Leishmania vaccine candidate, SP15, fused to monomeric red fluorescent protein (mDsRed) in its salivary glands. Importantly, mice bitten repeatedly by the transgenic mosquitoes raised anti-SP15 antibodies, indicating delivery of SP15 via blood feeding with its immunogenicity intact. Thus, this technology makes possible the generation of transgenic mosquitoes that match the original concept of a ,flying vaccinator'. However, medical safety issues and concerns about informed consent mitigate the use of the ,flying vaccinator' as a method to deliver vaccines. We propose that this expression system could be applied to elucidate saliva,malaria sporozoite interactions. [source] Energy,momentum consistent finite element discretization of dynamic finite viscoelasticityINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2010M. Groß Abstract This paper is concerned with energy,momentum consistent time discretizations of dynamic finite viscoelasticity. Energy consistency means that the total energy is conserved or dissipated by the fully discretized system in agreement with the laws of thermodynamics. The discretization is energy,momentum consistent if also momentum maps are conserved when group motions are superimposed to deformations. The performed approximation is based on a three-field formulation, in which the deformation field, the velocity field and a strain-like viscous internal variable field are treated as independent quantities. The new non-linear viscous evolution equation satisfies a non-negative viscous dissipation not only in the continuous case, but also in the fully discretized system. The initial boundary value problem is discretized by using finite elements in space and time. Thereby, the temporal approximation is performed prior to the spatial approximation in order to preserve the stress objectivity for finite rotation increments (incremental objectivity). Although the present approach makes possible to design schemes of arbitrary order, the focus is on finite elements relying on linear Lagrange polynomials for the sake of clearness. The discrete energy,momentum consistency is based on the collocation property and an enhanced second Piola,Kirchhoff stress tensor. The obtained coupled non-linear algebraic equations are consistently linearized. The corresponding iterative solution procedure is associated with newly proposed convergence criteria, which take the discrete energy consistency into account. The iterative solution procedure is therefore not complicated by different scalings in the independent variables, since the motion of the element is taken into account for solving the viscous evolution equation. Representative numerical simulations with various boundary conditions show the superior stability of the new time-integration algorithm in comparison with the ordinary midpoint rule. Both the quasi-rigid deformations during a free flight, and large deformations arising in a dynamic tensile test are considered. Copyright © 2009 John Wiley & Sons, Ltd. [source] From quantum chemistry and the classical theory of polar liquids to continuum approximations in molecular mechanics calculations,INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 5 2005Sergio A. Hassan Abstract Biological macromolecules and other polymers belong to the class of mesoscopic systems, with characteristic length scale of the order of a nanometer. Although microscopic models would be the preferred choice in theoretical calculations, their use in computer simulations becomes prohibitive for large systems or long simulation times. On the other hand, the use of purely macroscopic models in the mesoscopic domain may introduce artifacts, with effects that are difficult to assess and that may compromise the reliability of the calculations. Here is proposed an approach with the aim of minimizing the empirical nature of continuum approximations of solvent effects within the scope of molecular mechanics (MM) approximations in mesoscopic systems. Using quantum chemical methods, the potential generated by the molecular electron density is first decomposed in a multicenter-multipole expansion around predetermined centers. The monopole and dipole terms of the expansion at each site create electric fields that polarize the surrounding aqueous medium whose dielectric properties can be described by the classical theory of polar liquids. Debye's theory allows a derivation of the dielectric profiles created around isolated point charges and dipoles that can incorporate Onsager reaction field corrections. A superposition of screened Coulomb potentials obtained from this theory makes possible a simple derivation of a formal expression for the total electrostatic energy and the polar component of the solvation energy of the system. A discussion is presented on the physical meaning of the model parameters, their transferability, and their convergence to calculable quantities in the limit of simple systems. The performance of this continuum approximation in computer calculations of amino acids in the context of an atomistic force field is discussed. Applications of a continuum model based on screened Coulomb potentials in multinanosecond simulations of peptides and proteins are briefly reviewed. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source] Symplectic molecular dynamics integration using normal mode analysisINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 1 2001anka Jane Abstract The split integration symplectic method (SISM) for molecular dynamics (MD) integration using normal mode analysis based on a factorization of the Liouville propagator is presented. This approach is quite distinct from others that use fractional-step methods, owing to the analytical treatment of high-frequency motions. The method involves splitting the total Hamiltonian of the system into a harmonic part and the remaining part. Then the Hamilton equations are solved using a second-order generalized leapfrog integration scheme in which the purely harmonic Hamiltonian (which represents the main contribution of the chemical bonds and angles) is treated analytically, i.e., independent of the step size of integration, by a normal mode analysis that is carried out only once, at the beginning of calculation. The whole integration step combines analytical evolution of the harmonic part of the Hamiltonian with a correction arising from the remaining part. The proposed algorithm requires only one force evaluation per integration step. The algorithm was tested on a simple system of linear chain molecules. Results demonstrate the method makes possible the integration of the MD equations over larger time steps without loss of stability while being economical in computer time. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 84: 2,12, 2001 [source] Revisiting N -continuous density-functional theory: Chemical reactivity and "Atoms" in "Molecules"ISRAEL JOURNAL OF CHEMISTRY, Issue 3-4 2003Morrel H. Cohen We construct an internally-consistent density-functional theory valid for noninteger electron numbers N by precise definition of a density functional that is continuous in N. In this theory, charge transfer between the atoms of a heteronuclear diatomic molecule, which have been separated adiabatically to infinity, is avoided because the hardness for fractional occupation of a single HOMO spin-orbital is negative. This N -continuous density functional makes possible a variational theory of "atoms" in "molecules" that exactly decomposes the molecular electron density into a sum of contributions from its parts. The parts are treated as though isolated. That theory, in turn, gives a deep foundation to the chemical reactivity theory provided that the hardness of entities with vanishing spin density is positive, as argued to be the case here. This transition from negative to positive hardness closely parallels the transition from the Heitler-London to the Hund-Mulliken picture of molecular bonding. [source] Surface wound healing: a new, general function of eukaryotic cellsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 3 2003J. Meldolesi Abstract The ability to repair surface wounds is a property, necessary for long-term survival, expressed to various extents by all eukaryotic cell types except erythrocytes. The process is based on the rapid Ca2+ -induced exocytosis of various types of specific organelles, such as lysosomes and enlargeosomes, that decreases surface tension and makes possible the spontaneous fusion of lipid monolayers at the lesion edges. The recognized importance of the process in physiology and in several cases of pathology is discussed. [source] Intramolecular interactions and intramolecular hydrogen bonding in conformers of gaseous glycineJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 7 2001L. F. Pacios Abstract Ab initio calculations at the MP2/6-311++G** level of theory led recently to the identification of 13 stable conformers of gaseous glycine with relative energies within 11 kcal/mol. The stability of every structure depends on subtle intramolecular effects arising from conformational changes. These intramolecular interactions are examined with the tools provided by the Atoms In Molecules (AIM) theory, which allows obtaining a wealth of quantum mechanics information from the molecular electron density ,(r). The analysis of the topological features of ,(r) on one side and the atomic properties integrated in the basins defined by the gradient vector field of the density on the other side makes possible to explore the different intramolecular effects in every conformer. The existence of intramolecular hydrogen bonds on some conformers is demonstrated, while the presence of other stabilizing interactions arising from favorable conformations is shown to explain the stability of other structures in the potential energy surface of glycine. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 702,716, 2001 [source] The Political Economy of Shock TherapyJOURNAL OF ECONOMIC SURVEYS, Issue 1 2002John Marangos The collapse of the centrally administered economies gave rise to a transition process towards economic systems based on market relations. Nevertheless, the transition process is not restricted to the economic field. The political and ideological aspects of the transformation are fundamental. As such an analysis of the shock therapy model requires the exposition of what I define the primary elements of the shock therapy model which are: 1) The body of economic analysis used by the shock therapy model. 2) What structure of society the shock therapy model desires to achieve? 3) The speed of the reforms. 4) The political structure consistent with the model. 5) The consistent ideological structure. After the identification of the primary elements of the shock therapy model the next'step'is to identify secondary elements, the desired changes with respect to: 1) 'Price liberalisation,stabilisation. 2) Privatisation. 3) Institutional structure. 4) 'Monetary policy. 5) Fiscal policy. 6) International trade and Foreign Aid. 7) 'Social policy. The analytical framework developed makes possible to understand the shock therapy model from a new and more enlightening perspective. We are better able to comprehend the complexities involved and the disagreements about the reform process. [source] Women's readiness to follow milk product consumption recommendations: design and evaluation of a ,stage of change' algorithmJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2001P. Gulliver Objective To investigate readiness to follow milk product consumption recommendations in two random samples of New Zealand women, using an algorithm designed and evaluated to assess the stage of change construct of the Transtheoretical Model. Protocol Women were classified according to stage of readiness to perform two goal behaviours: consumption of two or four servings of milk products per day. Stage classification, as determined by the algorithm, was evaluated by estimating mean calcium intake in each stage using a validated food frequency questionnaire. This was undertaken in two independent samples of women randomly selected from the electoral rolls of two cities in New Zealand's South Island. Results Over 60% of women were classified as maintaining an intake of two servings of milk products per day. Of those women not meeting the goal of two servings per day, 73% had no intention of increasing their consumption. Over 80% of women were in the precontemplation stage for consuming four servings of milk products per day. Mean calcium intakes were significantly higher in women classified in action and maintenance stages than in preaction stages of change for both goal behaviours. Conclusion Of those women not currently meeting the recommendation for two servings of milk products per day, most are in precontemplation, a stage characterized by resistance to change. Use of the staging algorithm developed in this study makes possible the classification of women according to their readiness to change, and thus the provision of appropriate stage-tailored advice. [source] A new gadolinium-based contrast agent for magnetic resonance imaging of brain tumors: Kinetic study on a C6 rat glioma modelJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2001Emmanuel Fonchy Abstract T1 -weighted magnetic resonance imaging (MRI) was used to evaluate the potential interest of a new Gd-based contrast agent, termed P760, to characterize brain tumor heterogeneity and vascularization and to delineate regions containing permeable vessels. The C6 rat glioma model was used as a model of high-grade glioblastoma. The signal enhancement was measured as a function of time in the vascular compartment and in different regions of interest (ROIs) within the tumor after the injection of 0.02 mmol kg,1 of P760. The results were compared to those obtained after the injection of 0.1 mmol kg,1 of Gd-DOTA. We showed that P760, in spite of a Gd concentration five times smaller, produces an enhancement in the blood pool similar to that produced by Gd-DOTA. It was shown that P760 makes possible an excellent delineation of regions containing vessels with a damaged blood-brain barrier (BBB). Images acquired 5,10 minutes after P760 injection showed the location of permeable vessels more accurately than Gd-DOTA-enhanced images. The enhancement produced in the tumor by P760 was, however, less than that produced by Gd-DOTA. The extravasation and/or diffusion rate of P760 in the interstitial medium were found to be strongly reduced, compared to those found with Gd-DOTA. This study suggests that the new contrast agent has promising capabilities in clinical imaging of brain tumors. J. Magn. Reson. Imaging 2001;14:97,105. © 2001 Wiley-Liss, Inc. [source] Beyond the Dilemma of Difference: The Capability Approach to Disability and Special Educational NeedsJOURNAL OF PHILOSOPHY OF EDUCATION, Issue 3 2005Lorella Terzi In her recent pamphlet Special Educational Needs: a new look (2005) Mary Warnock has called for a radical review of special needs education and a substantial reconsideration of the assumptions upon which the current educational framework is based. The latter, she maintains, is hindered by a contradiction between the intention to treat all learners as the same and that of responding adequately to the needs arising from their individual differences. The tension highlighted by Warnock, which is central to the debate in special and inclusive education, is also referred to as the ,dilemma of difference'. This consists in the seemingly unavoidable choice between, on the one hand, identifying children's differences in order to provide for them differentially, with the risk of labelling and dividing, and, on the other, accentuating the ,sameness' and offering common provision, with the risk of not making available what is relevant to, and needed by, individual children. In this paper, I argue that the capability approach developed by Amartya Sen provides an innovative and important perspective for re-examining the dilemma of difference in significant ways. In particular, I maintain that reconceptualising disability and special needs through the capability approach makes possible the overcoming of the tension at the core of the dilemma of difference, whilst at the same time inscribing the debate within an ethical, normative framework based upon justice and equality. [source] Nucleophilic and acid catalyst behavior of a protic ionic liquid in a molecular reaction media.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 5 2009Part Abstract This work presents a new approach using ionic liquids, namely ethylammonium nitrate. The aim was to analyze how the addition of small amounts of a protic ionic liquid to a pure molecular solvent, modifies the microscopic characteristics of a reaction medium. In order to achieve this, a kinetic study of nucleophilic aromatic substitution reactions between 1-fluoro-2,4-dinitrobenzene and 1-butylamine or piperidine was developed in this type of binary mixtures. We have detected nucleophiles competition originated by the presence of the ionic solvent at very low concentrations, observing the ethylamine derivative as the main substitution product. Moreover, in the light of previous results we have confirmed that the protic ionic liquid can act as both Brönsted acid and/or nucleophile. In this connection, we have selected the nucleophilic addition of amines to carbonyl compounds as reaction model. The protic ionic liquid in the presence of aromatic aldehydes substituted by electron-donating groups makes possible the formation of the corresponding imines with good yields. The results demonstrated that the influence of the protic ionic liquid is very important in the course of both reaction systems. Copyright © 2008 John Wiley & Sons, Ltd. [source] Styrene/1,3-butadiene copolymerization by C2 -symmetric group 4 metallocenes based catalystsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 4 2008Mariagrazia Napoli Abstract C2 -symmetric group 4 metallocenes based catalysts (rac -[CH2(3- tert -butyl-1-indenyl)2]ZrCl2(1), rac -[CH2(1-indenyl)2]ZrCl2(2) and rac -[CH2(3- tert -butyl-1-indenyl)2]TiCl2(3)) are able to copolymerize styrene and 1,3-butadiene, to give products with high molecular weight. In agreement with symmetry properties of metallocene precatalysts, styrene homosequences are in isotactic arrangements. Full determination of microstructure of copolymers was obtained by 13C NMR and FTIR analysis and it reveals that insertion of butadiene on styrene chain-end happens prevailingly with 1,4- trans configuration. In the butadiene homosequences, using zirconocene-based catalysts, the 1,4- trans arrangement is favored over 1,4- cis, but the latter is prevailing in the presence of titanocene (3). Diad composition analysis of the copolymers makes possible to estimate the reactivity ratios of copolymerization: zirconocenes (1) and (2) produced copolymers having r1 × r2 = 0.5 and 3.0, respectively (where 1 refers to styrene and 2 to butadiene); while titanocene (3) gave tendencially blocky styrene,butadiene copolymers (r1 × r2 = 8.5). The copolymers do not exhibit crystallinity, even when they contain a high molar fraction of styrene. Probably, comonomer homosequences are too short to crystallize (ns = 16, in the copolymer at highest styrene molar fraction). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1476,1487, 2008 [source] A Combination of Selective Light Reflection and Fluorescence Modulation in a Cholesteric Polymer MatrixMACROMOLECULAR RAPID COMMUNICATIONS, Issue 3 2005Dasha Medvedeva Abstract Summary: The phase behavior and optical properties of a cholesteric ternary copolymer, containing nematogenic phenylbenzoate, cholesteric, and photochromic diarylethene side groups, and its mixture with 2 wt.-% fluorescent dopant were studied. The investigation of the kinetics of a photochemical opening-cycle process of the photochromic groups in the cholesteric mixture proved the energy transfer from the fluorescent dopant to the photochromic diarylethene groups. It was shown that the fluorescence intensity of the fluorescent dopant could be controlled by the portion of the "closed" form of the diarylethene groups. During the photocyclization of the photochromic groups a "degeneration" of the selective light reflection of the cholesteric matrix is observed. Fluorescence-resonance energy transfer makes possible the process of photosensitization of the back ring-opening photoreaction of the photochromic diarylethene groups in the cholesteric polymer matrix. [source] Diffractive optical elements with square concentric rings of equal widthMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2010Javier Alda Abstract A diffractive optical element having equal-width concentric square rings is analyzed in this article. This constant width makes possible its realization using spatial light modulators or square pixels phase screens. It allows a simple analytical treatment, and the element is also simulated using the Rayleigh-Sommerfeld approach. An experimental verification of its performance has been compared with the simulated results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:930,934, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25065 [source] | |||||||||||||||||||||||||||||||