902 resultados para Synthetic and analytic methods


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In Czech schools two teaching methods of reading are used: the analytic-synthetic (conventional) and genetic (created in the 1990s). They differ in theoretical foundations and in methodology. The aim of this paper is to describe the above mentioned theoretical approaches and present the results of study that followed the differences in the development of initial reading skills between these methods. A total of 452 first grade children (age 6-8) were assessed by a battery of reading tests at the beginning and at the end of the first grade and at the beginning of the second grade. 350 pupils participated all three times. Based on data analysis the developmental dynamics of reading skills in both methods and the main differences in several aspects of reading abilities (e.g. the speed of reading, reading technique, error rate in reading) are described. The main focus is on the reading comprehension development. Results show that pupils instructed using genetic approach scored significantly better on used reading comprehension tests, especially in the first grade. Statistically significant differences occurred between classes independently of each method. Therefore, other factors such as teacher´s role and class composition are discussed.

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The thesis as a whole argues that Spinoza’s Ethics in both method and content is aimed at the normal, partly rational person. Chapter 1 is on Spinoza’s writing style, finding that rather than being arid and technical, it aims to convince the reader by means of various rhetorical techniques, so does not assume an already rational reader. The following chapters of Part 1 examine whether the Ethics’ use of the synthetic geometric method exposes it to Descartes’ critique of that method in the “Second Replies” to his Meditations, that it is not suitable for pedagogy. This involves a consideration of the role of the TIE, finding in that early text not the analytic wing of a two-part analytic-synthetic method, but rather a defence and necessitation of a stand-alone synthetic method. Part 2 of the thesis develops this study of Spinoza’s writing for the common man to consider whether he is writing about the common man. This is done by examining one of the seemingly most abstract propositions in the Ethics, 4P72, which claims that a free man will not deceive even to save his own life. The study examines who exactly is this “free man” and what is his role in the Ethics. The study looks at the examples of free men in the TTP and at the concept of the model in the Ethics, and finds that rather than the free man being an impossible ideal which we can aim at but never achieve, everyone is free to some extent, and that even normal people are at times “the free man”.

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The reaction of 2,6-diformylpyridine-bis(benzoylhydrazone) [dfpbbh] and 2,6-diformylpyridine-bis(4-phenylsemicarbazone) [dfpbpsc] with lanthanides salts yielded the new chelates complexes [Eu(dfpbpsc-H +) 2]NO 3 (1), [Dy(fbhmp) 2][Dy(dfpbbh-2H +) 2]·2EtOH·2H 2O (fbhmp = 2-formylbenzoylhydrazone-6-methoxide-pyridine; Ph = phenyl; Py = pyridine; Et = ethyl) and [Er 2(dfpbbh-2H +) 2(μ-NO 3)(H 2O) 2(OH)]·H 2O. X-ray diffraction analysis was employed for the structural characterization of the three chelate complexes. In the case of complex 1, optical, synthetic and computational methods were also exploited for ground state structure determinations and triplet energy level of the ligand and HOMO-LUMO calculations, as well as for a detailed study of its luminescence properties. © 2010 Elsevier Ltd. All rights reserved.

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This qualitative research was performed with the goal of investigating the contributions of theoretical and methodological perspectives in the alphabetization process, aiming to train proficient writers of texts with communicative function. Hence, such were the goals established for this research: giving a retrospective look on the synthetic and analytic methods of teaching literacy; verifying the possibilities and limits of theoretical and methodological approaches of acquiring the ability to write and identifying the teachers’ ideas concerning basic concepts (such as literacy, text and textual genres) imbued in the teaching of writing; and establishing which activities they develop in the course of teaching whether the pedagogical practices of the teacher observed contributed to the formation of students who were capable of producing significant texts of diverse genres, suitable to the objectives, to the readers, and to the context of the circulation of texts. The research was done in a public elementary school, in a 2nd grade class of the city of Jaú. Subjects of the research were four teachers and twenty-eight children. For this work, two instruments were used for data collecting: a questionnaire and direct observation, registered in research diaries. Among the observations made were that, although there are many studies on literacy, the practices actually adopted in class are empirical in nature and do not contribute to the process of developing individual writing or reading skills at all; rather, it is only valued the ability of establishing relations between phonemes and graphemes; literacy teachers do not have adequate knowledge of concepts of literacy, teaching, text and textual genres, valuing only one methodological theory and disregarding other contributions on the field of text production

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The understanding of biological membranes may be improved by investigating physical properties of vesicles from natural or synthetic amphiphiles. The application of vesicles as mimetic agents depends on the knowledgment of their structure and properties. Vesicles having different curvature and size may be obtained using different preparation protocols. We have used differential scanning calorimetry (DSC) and steady-state fluorescence to investigate the gel to liquid-crystal phase transition of vesicles prepared by sonication (SUV) and non-sonication (GUV) of the synthetic dioctadecyldimethylammonium bromide (DODAB) in aqueous solution. DSC thermograms for a non-sonicated dispersion show a well-defined pre- and main transition corresponding to two narrow peaks at 36 and 45°C in the first upscan, while in a second upscan, only the main peak was observed. The sharpness of the peaks indicate a cooperative phase behavior for GUV. For a sonicated DODAB dispersion, the first upscan shows a third peak at 40.3°C, whereas for the second upscan the peaks are not well-defined, indicating a less cooperative phase behavior. Alternatively, the fluorescence quantum yield (Φ f) and the anisotropy (r) of trans, trans, trans-1-[4-(3-carboxypropyl)-phenyl]-6-[4-butylphenyl]-1,3,5-hexatriene (4H4A) and the ratio I 1/I 3 of the first to the third vibronic peaks of the pyrene emission spectrum as function of temperature are used as well to describe the phase behavior of DODAB sonicated and non-sonicated dispersions. It is in good agreement with the DSC results that the cooperativity of the thermotropic process is diminished under sonication of the DODAB dispersion, meaning that sonication changes from homogeneous to heterogeneous populations of the amphiphile aggregates. The pre- and main transitions obtained from these techniques are in fairly good accord with results from the literature.

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The longitudinal dimension of schizophrenia and related severe mental illness is a key component of theoretical models of recovery. However, empirical longitudinal investigations have been underrepresented in the psychopathology of schizophrenia. Similarly, traditional approaches to longitudinal analysis of psychopathological data have had serious limitations. The utilization of modern longitudinal methods is necessary to capture the complexity of biopsychosocial models of treatment and recovery in schizophrenia. The present paper summarizes empirical data from traditional longitudinal research investigating recovery in symptoms, neurocognition, and social functioning. Studies conducted under treatment as usual conditions are compared to psychosocial intervention studies and potential treatment mechanisms of psychosocial interventions are discussed. Investigations of rehabilitation for schizophrenia using the longitudinal analytic strategies of growth curve and time series analysis are demonstrated. The respective advantages and disadvantages of these modern methods are highlighted. Their potential use for future research of treatment effects and recovery in schizophrenia is also discussed.

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During the past three decades, the subject of fractional calculus (that is, calculus of integrals and derivatives of arbitrary order) has gained considerable popularity and importance, mainly due to its demonstrated applications in numerous diverse and widespread fields in science and engineering. For example, fractional calculus has been successfully applied to problems in system biology, physics, chemistry and biochemistry, hydrology, medicine, and finance. In many cases these new fractional-order models are more adequate than the previously used integer-order models, because fractional derivatives and integrals enable the description of the memory and hereditary properties inherent in various materials and processes that are governed by anomalous diffusion. Hence, there is a growing need to find the solution behaviour of these fractional differential equations. However, the analytic solutions of most fractional differential equations generally cannot be obtained. As a consequence, approximate and numerical techniques are playing an important role in identifying the solution behaviour of such fractional equations and exploring their applications. The main objective of this thesis is to develop new effective numerical methods and supporting analysis, based on the finite difference and finite element methods, for solving time, space and time-space fractional dynamical systems involving fractional derivatives in one and two spatial dimensions. A series of five published papers and one manuscript in preparation will be presented on the solution of the space fractional diffusion equation, space fractional advectiondispersion equation, time and space fractional diffusion equation, time and space fractional Fokker-Planck equation with a linear or non-linear source term, and fractional cable equation involving two time fractional derivatives, respectively. One important contribution of this thesis is the demonstration of how to choose different approximation techniques for different fractional derivatives. Special attention has been paid to the Riesz space fractional derivative, due to its important application in the field of groundwater flow, system biology and finance. We present three numerical methods to approximate the Riesz space fractional derivative, namely the L1/ L2-approximation method, the standard/shifted Gr¨unwald method, and the matrix transform method (MTM). The first two methods are based on the finite difference method, while the MTM allows discretisation in space using either the finite difference or finite element methods. Furthermore, we prove the equivalence of the Riesz fractional derivative and the fractional Laplacian operator under homogeneous Dirichlet boundary conditions – a result that had not previously been established. This result justifies the aforementioned use of the MTM to approximate the Riesz fractional derivative. After spatial discretisation, the time-space fractional partial differential equation is transformed into a system of fractional-in-time differential equations. We then investigate numerical methods to handle time fractional derivatives, be they Caputo type or Riemann-Liouville type. This leads to new methods utilising either finite difference strategies or the Laplace transform method for advancing the solution in time. The stability and convergence of our proposed numerical methods are also investigated. Numerical experiments are carried out in support of our theoretical analysis. We also emphasise that the numerical methods we develop are applicable for many other types of fractional partial differential equations.

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Groundwater management involves conflicting objectives as maximization of discharge contradicts the criteria of minimum pumping cost and minimum piping cost. In addition, available data contains uncertainties such as market fluctuations, variations in water levels of wells and variations of ground water policies. A fuzzy model is to be evolved to tackle the uncertainties, and a multiobjective optimization is to be conducted to simultaneously satisfy the contradicting objectives. Towards this end, a multiobjective fuzzy optimization model is evolved. To get at the upper and lower bounds of the individual objectives, particle Swarm optimization (PSO) is adopted. The analytic element method (AEM) is employed to obtain the operating potentio metric head. In this study, a multiobjective fuzzy optimization model considering three conflicting objectives is developed using PSO and AEM methods for obtaining a sustainable groundwater management policy. The developed model is applied to a case study, and it is demonstrated that the compromise solution satisfies all the objectives with adequate levels of satisfaction. Sensitivity analysis is carried out by varying the parameters, and it is shown that the effect of any such variation is quite significant. Copyright (c) 2015 John Wiley & Sons, Ltd.

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The research described in this thesis focuses, principally, on synthesis of stable α-diazosulfoxides and investigation of their reactivity under various reaction conditions (transition-metal catalysed, photochemical, thermal and microwave) with a particular emphasis on the reactive intermediates and mechanistic aspects of the reaction pathways involved. In agreement with previous studies carried out on these compounds, the key reaction pathway of α-diazosulfoxides was found to be hetero-Wolff rearrangement to give α-oxosulfine intermediates. However, a competing reaction pathway involving oxygen migration from sulfur to oxygen was also observed. Critically, isomerisation of α-oxosulfine stereoisomers was observed directly by 1H NMR spectroscopy in this work and this observation accounts for the stereochemical outcomes of the various cycloaddition reactions, whether carried out with in situ trapping or with preformed solutions of sulfines. Furthermore, matrix isolation experiments have shown that electrocyclisation of α-oxosulfines to oxathiiranes takes place and this verifies the proposed mechanisms for enol and disulfide formation. The introductory chapter includes a brief literature review of the synthesis and reactivity of α-diazosulfoxides prior to the commencement of research in this field by the Maguire group. The Wolff rearrangement is also discussed and the characteristic reactions of a number of reactive intermediates (sulfines, sulfenes and oxathiiranes) are outlined. The use of microwave-assisted organic synthesis is also examined, specifically, in the context of α-diazocarbonyl compounds as substrates. The second chapter describes the synthesis of stable monocyclic and bicyclic lactone derivatives of α-diazosulfoxides from sulfide precursors according to established experimental procedures. Approaches to precursors of ketone and sulfimide derivatives of α-diazosulfoxides are also described. The third chapter examines the reactivity of α-diazosulfoxides under thermal, microwave, rhodium(II)-catalysed and photochemical conditions. Comparison of the results obtained under thermal and microwave conditions indicates that there was no evidence for any effect, other than thermal, induced by microwave irradiation. The results of catalyst studies involving several rhodium(II) carboxylate and rhodium(II) carboxamidate catalysts are outlined. Under photochemical conditions, sulfur extrusion is a significant reaction pathway while under thermal or transition metal catalysed conditions, oxygen extrusion is observed. One of the most important observations in this work was the direct spectroscopic observation (by 1H NMR) of interconversion of the E and Z-oxosulfines. Trapping of the α-oxosulfine intermediates as cycloadducts by reaction with 2,3-dimethyl-1,3-butadiene proved useful both synthetically and mechanistically. As the stereochemistry of the α-oxosulfine is retained in the cycloadducts, this provided an ideal method for characterisation of this key feature. In the case of one α-oxosulfine, a novel [2+2] cycloaddition was observed. Preliminary experiments to investigate the reactivity of an α-diazosulfone under rhodium(II) catalysis and microwave irradiation are also described. The fourth chapter describes matrix isolation experiments which were carried out in Rühr Universität, Bochum in collaboration with Prof. Wolfram Sander. These experiments provide direct spectroscopic evidence of an α-oxosulfine intermediate formed by hetero-Wolff rearrangement of an α-diazosulfoxide and subsequent cyclisation of the sulfine to an oxathiirane was also observed. Furthermore, it was possible to identify which stereoisomer of the α-oxosulfine was present in the matrix. A preliminary laser flash photolysis experiment is also discussed. The experimental details, including all spectral and analytical data, are reported at the end of each chapter. The structural interpretation of 1H NMR spectra of the cycloadducts, described in Chapter 3, is discussed in Appendix I.

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Several natural and synthetic supports have been assessed for their efficiency for enzyme immobilization. Synthetic polymer materials are prepared by chemical polymerization using various monomers. As a kind of important carrier, synthetic polymer materials exhibit the advantages of good mechanical rigidity, high specific surface area, inertness to microbial attack, easy to change their surface characteristics, and their potential for bringing specific functional group according to actual needs. Hence, they have been widely investigated and used for enzyme immobilization. When it comes to the natural polymer materials, much attention has been paid to cellulose and other natural polymer materials owing to their wide range of sources, easy modification, nontoxic, and pollution-free, with a possibility of introducing wide variety of functional groups and good biocompatible properties. In this work report the use of synthetic polymer, polypyrrole and its derivatives and natural polymers coconut fiber and sugarcane bagasse as supports for Diastase α- amylase immobilization. An attempt was also made to functionalize both synthetic and natural polymers using Amino-propyl triethoxysilane. Supports and their immobilized forms were characterized via FT-IR, TG, SEM, XRD, BET and EDS techniques. Immobilization parameters were also optimized so as to prepare stable immobilized biocatalyst for starch hydrolysis.

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The goal of the review is to provide a state-of-the-art survey on sampling and probe methods for the solution of inverse problems. Further, a configuration approach to some of the problems will be presented. We study the concepts and analytical results for several recent sampling and probe methods. We will give an introduction to the basic idea behind each method using a simple model problem and then provide some general formulation in terms of particular configurations to study the range of the arguments which are used to set up the method. This provides a novel way to present the algorithms and the analytic arguments for their investigation in a variety of different settings. In detail we investigate the probe method (Ikehata), linear sampling method (Colton-Kirsch) and the factorization method (Kirsch), singular sources Method (Potthast), no response test (Luke-Potthast), range test (Kusiak, Potthast and Sylvester) and the enclosure method (Ikehata) for the solution of inverse acoustic and electromagnetic scattering problems. The main ideas, approaches and convergence results of the methods are presented. For each method, we provide a historical survey about applications to different situations.