Monte Carlo simulation of interface alloying

An Ising-like model, with interactions ranging up to next-nearest-neighbor pairs, is used to simulate the process of interface alloying. Interactions are chosen to stabilize an intermediate "antiferromagnetic" ordered structure. The dynamics proceeds exclusively by atom-vacancy exchanges. In order to characterize the process, the time evolution of the width of the intermediate ordered region and the diffusion length is studied. Both lengths are found to follow a power-law evolution with exponents depending on the characteristic features of the model.

Judicial Review of Academic Decisions

This thesis entitled “Judicial review of academic decisions.Education in India is being increasingly controlled and guided by the courts.This study makes an attempt to assess the involvement of the court in regulating education and its role or interference in the conventional concepts of ‘academic freedom’ and ‘university autonomy.The study mostly concentrates on the jurisdiction under Article 226 of the Constitution and its invocation in academic matters with particular reference to the decisions of the Kerala High Court.The concept of judicial review in the Constituent Assembly, initial approach of the Supreme Court of India towards the doctrine, gradual empowerment of Indian judiciary in this area and the resultant judicial activism.The study proceeds through the analysis of ‘academic freedom’ and ‘university autonomy’ in the 4"‘ chapter. This chapter attempts to probe academic freedom and university autonomy in India,England and United States and autonomy of Indian universities before and after independence.Basic principles and the jurisdictional parameters of judicial review in the area of academic decisions, as pronounced by the Apex Court, can be convincingly and consistently followed by the High Courts, which is possible only if special Academic Benches are constituted.

Model Diagnostics in the presence of measurement error

The problem of using information available from one variable X to make inferenceabout another Y is classical in many physical and social sciences. In statistics this isoften done via regression analysis where mean response is used to model the data. Onestipulates the model Y = µ(X) +ɛ. Here µ(X) is the mean response at the predictor variable value X = x, and ɛ = Y - µ(X) is the error. In classical regression analysis, both (X; Y ) are observable and one then proceeds to make inference about the mean response function µ(X). In practice there are numerous examples where X is not available, but a variable Z is observed which provides an estimate of X. As an example, consider the herbicidestudy of Rudemo, et al. [3] in which a nominal measured amount Z of herbicide was applied to a plant but the actual amount absorbed by the plant X is unobservable. As another example, from Wang [5], an epidemiologist studies the severity of a lung disease, Y , among the residents in a city in relation to the amount of certain air pollutants. The amount of the air pollutants Z can be measured at certain observation stations in the city, but the actual exposure of the residents to the pollutants, X, is unobservable and may vary randomly from the Z-values. In both cases X = Z+error: This is the so called Berkson measurement error model.In more classical measurement error model one observes an unbiased estimator W of X and stipulates the relation W = X + error: An example of this model occurs when assessing effect of nutrition X on a disease. Measuring nutrition intake precisely within 24 hours is almost impossible. There are many similar examples in agricultural or medical studies, see e.g., Carroll, Ruppert and Stefanski [1] and Fuller [2], , among others. In this talk we shall address the question of fitting a parametric model to the re-gression function µ(X) in the Berkson measurement error model: Y = µ(X) + ɛ; X = Z + η; where η and ɛ are random errors with E(ɛ) = 0, X and η are d-dimensional, and Z is the observable d-dimensional r.v.

4,5-Dihydro-1,3-dioxepine als chirale Bausteine in der enantioselektiven organischen Synthese

Durch asymmetrische Doppelbindungsisomerisierung mittels Me-DuPHOS-modifizierter Dihalogen-Nickel-Komplexe als Katalysatorvorstufen lassen sich aus 2-Alkyl-4,7-dihydro-1,3-dioxepinen hochenantiomerenreine 2-Alkyl-4,5-dihydro-1,3-dioxepine erhalten. Ein Ziel dieser Arbeit war es, die bisher noch unbekannte Absolutkonfiguration dieses Verbindungstyps zu bestimmen und darüber hinaus ihre Einsatzfähigkeit in der enantioselektiven organischen Synthese zu untersuchen. Zu diesem Zweck wurden enantiomerenangereichertes 2-Isopropyl- und 2-tert-Butyl-4,5-dihydro-1,3-dioxepin mit m-Chlorperbenzoesäure epoxidiert. Dabei bildeten sich die entsprechenden 3-Chlorbenzoesäure-(2-alkyl-5-hydroxy-1,3-dioxepan-4yl)-ester in hohen Ausbeuten und Diastereoselektivitäten. Von den vier zu erwartenden Diastereomeren wurden jeweils nur zwei mit einer Selektivität von mehr als 95:5 gebildet. Im Fall des 3-Chlorbenzoesäure-(2-isopropyl-5-hydroxy-1,3-dioxepan-4yl)-esters konnte das Haupt-diastereomer kristallin erhalten werden. Durch röntgenspektroskopische Untersuchung war es möglich, die Relativ-Konfiguration dieser Verbindung zu bestimmen. Die Ester lassen sich unter Ringverengung in 2-Alkyl-1,3-dioxan-4-carbaldehyde umlagern. Ausgehend von diesen Carbaldehyden stehen zwei Synthesewege zur Verfügung, welche zu Verbindungen führen deren Absolutkonfiguration bereits bekannt ist. So erhält man durch Reduktion 2-Alkyl-1,3-dioxan-4-yl-methanole, welche sich in 1,2,4-Butantriol überführen lassen. Oxidation ergibt die 2-Alkyl-1,3-dioxan-4-carbonsäuren, aus denen 3-Hydroxytetrahydrofuran-2-on gewonnen werden kann. Messung des Drehwertes dieser beiden literaturbekannten Verbindungen liefert nicht nur Information über deren Enantiomerenreinheit sondern ebenfalls über die Konfiguration ihres Stereozentrums. In Kombination mit der Relativ-Konfiguration des Esters ist somit ein Rückschluss auf die Absolutkonfiguration der eingesetzten 4,5-Dihydro-1,3-dioxepine möglich. Die auf den beschriebenen Wegen gewonnenen Substanzen finden Anwendung in der stereoselektiven organischen Synthese. Löst man die Chlorbenzoesäureester in Dichlormethan und behandelt sie mit wässriger Salzsäure, so entstehen die bicyclischen 2-Alkyltetrahydrofuro[2,3-d][1,3]dioxole. Auch bei diesen Verbindungen konnten hohe Enantio- und Diastereoselektivitäten erzielt werden. Der intermolekular verlaufende Reaktionsmechanismus der Bicyclus-Bildung, welcher unter Abspaltung eines den Alkylrest tragenden Aldehyds und dessen Neuanlagerung unter Ausbildung eines Acetals verläuft, konnte in dieser Arbeit durch ein Kreuzungsexperiment bestätigt werden. Umacetalisierung der Bicyclen liefert 2-Methoxytetrahydrofuran-3-ol, aus dem durch Acetalspaltung Tetrahydrofuran-2,3-diol erhalten wird, das die Halbacetalform der entsprechenden Desoxytetrose darstellt, die auf diese Weise in einer de novo-Synthese hergestellt werden kann.

Zur Synthese von alpha-Aminoaldehyden und Aminosäuren mit alpha-quartären Zentren durch Aziridinierung funktionalisierter Olefine

Ziel dieser Arbeit war, durch Aziridinierung homochiraler 5-Methyl-4H-1,3-dioxinen eine neue Methode zur Synthese von alpha-Aminoaldehyden und den ableitbaren Aminosäuren mit alpha-quartären Zentren zu entwickeln. Die chiralen 5-Methyl-4H-1,3-dioxine sind mit hohen Enantiomerenüberschüssen durch asymmetrische Doppelbindungsisomerisierung von 5-Methylen-1,3-dioxanen zugänglich. Die Metall-katalysierte Aziridinierung der 5-Methyl-4H-1,3-dioxine mit der Nitrenquelle (N-Tosylimino)phenyliodinan führte direkt zu N-Tosyl-geschützen 4-Methyl-1,3-oxazolidin-4-carbaldehyden. Vermutlich über ein Aziridin als nicht isolierbare Zwischenstufe werden über eine Ringöffnungs-/Ringverengungsreaktion die Oxazolidinderivate gebildet, vorzugsweise in Gegenwart von Cu(I)-Katalysatoren, während die Rhodium-katalysierte Reaktion ausschließlich zu Insertionsprodukten führt. In der Cu-katalysierten Aziridinierung ist das Verhältnis von Aziridinierung/Insertion abhängig von der Katalysatorkonzentration. Die Aziridinierung mit N-(p-Nitrobenzolsulfonyl)- und N-(Trimethylsilylethylsulfonyl)- substituierten Nitrenquellen führt zu Oxazolidinderivaten mit leichter abspaltbaren Schutzgruppen. Diese Nitrenquellen können in situ aus den korrespondierenden Sulfonamiden mit Iodosobenzol dargestellt werden. Bei dem Einsatz homochiraler 4H-1,3-Dioxine ist Erhalt der Stereoinformation abhängig vom Substituenten in 2-Position der Dioxine sowie von der Polarität des Lösungsmittels. Die höchsten Selektivitäten wurden in tert-Butylmethylether erzielt. In Falle des 2-tert-Butyl-4-methyl-3-(toluol-4-sulfonyl)-1,3-oxazolidin-4-carbaldehyds kristallisiert das Hauptdiastereomer in enantiomerenreiner Form. Die Absolutkonfiguration wurde durch Röntgenkristallstrukturanalyse ermittelt. Das Anwendungspotential dieser neuen Methode konnte durch Überführen der Serinale in Aminoalkohole und alpha-Methylserin-Derivate sowie in der Synthese der unnatürlichen Aminosäure alpha-Vinylalanin gezeigt werden.

Atomistic-continuum modeling of ultrafast laser-induced melting of silicon targets

In this work, we present an atomistic-continuum model for simulations of ultrafast laser-induced melting processes in semiconductors on the example of silicon. The kinetics of transient non-equilibrium phase transition mechanisms is addressed with MD method on the atomic level, whereas the laser light absorption, strong generated electron-phonon nonequilibrium, fast heat conduction, and photo-excited free carrier diffusion are accounted for with a continuum TTM-like model (called nTTM). First, we independently consider the applications of nTTM and MD for the description of silicon, and then construct the combined MD-nTTM model. Its development and thorough testing is followed by a comprehensive computational study of fast nonequilibrium processes induced in silicon by an ultrashort laser irradiation. The new model allowed to investigate the effect of laser-induced pressure and temperature of the lattice on the melting kinetics. Two competing melting mechanisms, heterogeneous and homogeneous, were identified in our big-scale simulations. Apart from the classical heterogeneous melting mechanism, the nucleation of the liquid phase homogeneously inside the material significantly contributes to the melting process. The simulations showed, that due to the open diamond structure of the crystal, the laser-generated internal compressive stresses reduce the crystal stability against the homogeneous melting. Consequently, the latter can take a massive character within several picoseconds upon the laser heating. Due to the large negative volume of melting of silicon, the material contracts upon the phase transition, relaxes the compressive stresses, and the subsequent melting proceeds heterogeneously until the excess of thermal energy is consumed. A series of simulations for a range of absorbed fluences allowed us to find the threshold fluence value at which homogeneous liquid nucleation starts contributing to the classical heterogeneous propagation of the solid-liquid interface. A series of simulations for a range of the material thicknesses showed that the sample width we chosen in our simulations (800 nm) corresponds to a thick sample. Additionally, in order to support the main conclusions, the results were verified for a different interatomic potential. Possible improvements of the model to account for nonthermal effects are discussed and certain restrictions on the suitable interatomic potentials are found. As a first step towards the inclusion of these effects into MD-nTTM, we performed nanometer-scale MD simulations with a new interatomic potential, designed to reproduce ab initio calculations at the laser-induced electronic temperature of 18946 K. The simulations demonstrated that, similarly to thermal melting, nonthermal phase transition occurs through nucleation. A series of simulations showed that higher (lower) initial pressure reinforces (hinders) the creation and the growth of nonthermal liquid nuclei. For the example of Si, the laser melting kinetics of semiconductors was found to be noticeably different from that of metals with a face-centered cubic crystal structure. The results of this study, therefore, have important implications for interpretation of experimental data on the kinetics of melting process of semiconductors.

Molecular computations for reactions and phase transitions: applications to protein stabilization, hydrates and catalysis

In this work we have made significant contributions in three different areas of interest: therapeutic protein stabilization, thermodynamics of natural gas clathrate-hydrates, and zeolite catalysis. In all three fields, using our various computational techniques, we have been able to elucidate phenomena that are difficult or impossible to explain experimentally. More specifically, in mixed solvent systems for proteins we developed a statistical-mechanical method to model the thermodynamic effects of additives in molecular-level detail. It was the first method demonstrated to have truly predictive (no adjustable parameters) capability for real protein systems. We also describe a novel mechanism that slows protein association reactions, called the “gap effect.” We developed a comprehensive picture of methioine oxidation by hydrogen peroxide that allows for accurate prediction of protein oxidation and provides a rationale for developing strategies to control oxidation. The method of solvent accessible area (SAA) was shown not to correlate well with oxidation rates. A new property, averaged two-shell water coordination number (2SWCN) was identified and shown to correlate well with oxidation rates. Reference parameters for the van der Waals Platteeuw model of clathrate-hydrates were found for structure I and structure II. These reference parameters are independent of the potential form (unlike the commonly used parameters) and have been validated by calculating phase behavior and structural transitions for mixed hydrate systems. These calculations are validated with experimental data for both structures and for systems that undergo transitions from one structure to another. This is the first method of calculating hydrate thermodynamics to demonstrate predictive capability for phase equilibria, structural changes, and occupancy in pure and mixed hydrate systems. We have computed a new mechanism for the methanol coupling reaction to form ethanol and water in the zeolite chabazite. The mechanism at 400°C proceeds via stable intermediates of water, methane, and protonated formaldehyde.

SLAM using an Imaging Sonar for Partially Structured Underwater Environments

In this paper we describe a system for underwater navigation with AUVs in partially structured environments, such as dams, ports or marine platforms. An imaging sonar is used to obtain information about the location of planar structures present in such environments. This information is incorporated into a feature-based SLAM algorithm in a two step process: (I) the full 360deg sonar scan is undistorted (to compensate for vehicle motion), thresholded and segmented to determine which measurements correspond to planar environment features and which should be ignored; and (2) SLAM proceeds once the data association is obtained: both the vehicle motion and the measurements whose correct association has been previously determined are incorporated in the SLAM algorithm. This two step delayed SLAM process allows to robustly determine the feature and vehicle locations in the presence of large amounts of spurious or unrelated measurements that might correspond to boats, rocks, etc. Preliminary experiments show the viability of the proposed approach

Terapia cognitivo comportamental para el manejo de la fibromialgia

La presente es una revisión teórica inicial acerca de la terapia cognitivo comportamental para el manejo de la fibromialgia. Para llegar a su descripción y demostración de su evidencia, se realiza una breve definición y contextualización del síndrome denominado fibromialgia. Se trata de un síndrome doloroso, crónico, complejo y multideterminado, que afecta considerablemente la calidad de vida de las personas que lo desarrollan. Su manejo es igualmente complejo. En consideración a ello, se procede a hacer una descripción igualmente breve de la multiplicidad de terapias psicológicas que se realizan para tratarla y se hace un mayor énfasis en la terapia cognitivo comportamental, demostrándose su evidencia en el manejo efectivo del dolor crónico y el comportamiento de este tipo de pacientes.

Análisis sectorial del GSED

El Grupo Social Empresarial de la Defensa GSED es el ente encargado de dirigir y orientar las políticas corporativas de las empresas que constituyen el Ministerio de Defensa, con el único fin de contribuir paz y seguridad en el territorio Colombiano. Aunque el grupo no es reconocido como tal sino por las empresas que lo componen se define al grupo para la comprensión de los lectores del presente trabajo. De igual forma se explica y analiza el objeto y función de las mismas Por medio de un análisis de la estructura del grupo, abarcando ejes como el administrativo y financiero se determina el impacto del mismo y su importancia en la economía del país como Grupo Empresarial.

Incidencia de la explotación minera en la disputa territorial en el municipio de Segovia. 2002-2010

El interés de la presente investigación está sostenido en analizar la estructuración de la política pública minero-energética, los instrumentos utilizados para su posterior implementación en el municipio de Segovia, Antioquia, y la incidencia que tiene en las tensiones de los actores que tienen presencia en este lugar. Se utiliza la Acumulación por Desposesión para la interpretación de los hechos ocurridos en Segovia, donde se procede a evidenciar que la imposición o inclusión de nuevos modos de producción, genera resistencias que entran en disputa entre sí y que producen la reconfiguración espacial del municipio.

Gestão e trabalhadores do conhecimento em Tecnologias da informação (UML)

RESUMO: O conhecimento existe desde sempre, mesmo num estado latente condicionado algures e apenas à espera de um meio (de uma oportunidade) de se poder manifestar. O conhecimento é duplamente um fenómeno da consciência: porque dela procede num dado momento da sua vida e da sua história e porque só nela termina, aperfeiçoando-a e enriquecendo-a. O conhecimento está assim em constante mudança. À relativamente pouco tempo começou-se a falar de Gestão do Conhecimento e na altura foi muito associada às Tecnologias da Informação, como meio de colectar, processar e armazenar cada vez mais, maiores quantidades de informação. As Tecnologias da Informação têm tido, desde alguns anos para cá, um papel extremamente importante nas organizações, inicialmente foram adoptadas com o propósito de automatizar os processos operacionais das organizações, que suportam as suas actividades quotidianas e nestes últimos tempos as Tecnologias da Informação dentro das organizações têm evoluído rapidamente. Todo o conhecimento, mesmo até o menos relevante de uma determinada área de negócio, é fundamental para apoiar o processo de tomada de decisão. As organizações para atingirem melhores «performances» e conseguirem transcender as metas a que se propuseram inicialmente, tendem a munir-se de mais e melhores Sistemas de Informação, assim como, à utilização de várias metodologias e tecnologias hoje em dia disponíveis. Por conseguinte, nestes últimos anos, muitas organizações têm vindo a demonstrar uma necessidade crucial de integração de toda a sua informação, a qual está dispersa pelos diversos departamentos constituintes. Para que os gestores de topo (mas também para outros funcionários) possam ter disponível em tempo útil, informação pertinente, verdadeira e fiável dos negócios da organização que eles representam, precisam de ter acesso a bons Sistemas de Tecnologias de Informação. Numa acção de poderem agir mais eficazmente e eficientemente nas tomadas de decisão, por terem conseguido tirar por esses meios o máximo de proveito possível da informação, e assim, apresentarem melhores níveis de sucesso organizacionais. Também, os Sistemas de «Business Intelligence» e as Tecnologias da Informação a ele associadas, utilizam os dados existentes nas organizações para disponibilizar informação relevante para as tomadas de decisão. Mas, para poderem alcançar esses níveis tão satisfatórios, as organizações necessitam de recursos humanos, pois como podem elas serem competitivas sem Luís Miguel Borges – Gestão e Trabalhadores do Conhecimento em Tecnologias da Informação (UML) ULHT – ECATI 6 trabalhadores qualificados. Assim, surge a necessidade das organizações em recrutar os chamados hoje em dia “Trabalhadores do Conhecimento”, que são os indivíduos habilitados para interpretar as informações dentro de um domínio específico. Eles detectam problemas e identificam alternativas, com os seus conhecimentos e discernimento, eles trabalham para solucionar esses problemas, ajudando consideravelmente as organizações que representam. E, usando metodologias e tecnologias da Engenharia do Conhecimento como a modelação, criarem e gerirem um histórico de conhecimento, incluindo conhecimento tácito, sobre várias áreas de negócios da organização, que podem estar explícitos em modelos abstractos, que possam ser compreendidos e interpretados facilmente, por outros trabalhadores com níveis de competência equivalentes. ABSTRACT: Knowledge has always existed, even in a latent state conditioning somewhere and just waiting for a half (an opportunity) to be able to manifest. Knowledge is doubly a phenomenon of consciousness: because proceeds itself at one point in its life and its history and because solely itself ends, perfecting it and enriching it. The knowledge is so in constant change. In the relatively short time that it began to speak of Knowledge Management and at that time was very associated with Information Technologies, as a means to collect, process and store more and more, larger amounts of information. Information Technologies has had, from a few years back, an extremely important role in organizations, were initially adopted in order to automate the operational processes of organizations, that support their daily activities and in recent times Information Technologies within organizations has evolved rapidly. All the knowledge, even to the least relevant to a particular business area, is fundamental to support the process of decision making. The organizations to achieve better performances and to transcend the goals that were initially propose, tend to provide itself with more and better Information Systems, as well as, the use of various methodologies and technologies available today. Consequently, in recent years, many organizations have demonstrated a crucial need for integrating all their information, which is dispersed by the diver constituents departments. For top managers (but also for other employees) may have ready in time, pertinent, truthful and reliable information of the organization they represent, need access to good Information Technology Systems. In an action that they can act more effectively and efficiently in decision making, for having managed to get through these means the maximum possible advantage of the information, and so, present better levels of organizational success. Also, the systems of Business Intelligence and Information Technologies its associated, use existing data on organizations to provide relevant information for decision making. But, in order to achieve these levels as satisfactory, organizations need human resources, because how can they be competitive without skilled workers. Thus, arises the need for organizations to recruit called today “Knowledge Workers”, they are the individuals enable to interpret the information within a specific domain. They detect problems and identify alternatives, with their knowledge and discernment they work to solve these problems, helping considerably the organizations that represent. And, using Luís Miguel Borges – Gestão e Trabalhadores do Conhecimento em Tecnologias da Informação (UML) ULHT – ECATI 8 methodologies and technologies of Knowledge Engineering as modeling, create and manage a history of knowledge, including tacit knowledge, on various business areas of the organization, that can be explicit in the abstract models, that can be understood and interpreted easily, by other workers with equivalent levels of competence.

Using eye-tracking to detect reading difficulties

Taking into account the study of Luegi (2006), where eye movements of 20 Portuguese university students while reading text passages were analyzed, in this article we discuss some methodological issues concerning eye tracking measures to evaluate reading difficulties. Relating syntactic complexity, grammaticality and ambiguity to eye movements, we will discuss the use of many different dependent variables that indicate the immediate and delayed processes in text processing. We propose a new measure that we called Progression-Path which permits analyzing, in the critical region, what happens when the reader proceeds on the sentence instead of going backwards to solve a problem that s/he found (which is the most common expected behavior but not the only one, as is illustrated by some of our examples).

Fagoterapia como alternativa ao uso dos antibióticos convencionais

Nas últimas décadas, a investigação de antibióticos com novos mecanismos de acção, tem vindo a ser motivada pela contínua emergência de estirpes bacterianas multirresistentes. No entanto, nos últimos anos esse desenvolvimento tem vindo a abrandar, o que representa um grave problema de saúde pública. Antes da era dos antibióticos a fagoterapia representava a terapêutica de primeira linha no tratamento de infecções bacterianas. Como a ausência de recursos impossibilitava a compreensão dos mecanismos de acção moleculares do fago, a fagoterapia era apenas sustentada pelo conhecimento empírico. A ausência de conhecimento associada ao início da era dos antibióticos foram condições suficientes para que a terapêutica fágica fosse posta de parte, à excepção de alguns países da Europa do Leste. De acordo com a literatura disponibilizada por estes países, vários têm sido os casos de sucesso no tratamento de infecções bacterianas, incluindo infecções causadas por estirpes multirresistentes aos antibióticos convencionais. No entanto, contrariamente aos ensaios clínicos, a maioria destes estudos omite informação crítica que impossibilita a interpretação dos respectivos resultados. Actualmente, as novas ferramentas oferecidas pelos avanços biotecnológicos possibilitam não só a compreensão do mecanismo de infecção bacteriana como também permitem compreender melhor a interacção entre os bacteriófagos e o organismo humano. Como tal, no futuro, a fagoterapia pode ser considerada uma alternativa efectiva para solucionar os casos críticos de multirresistência bacteriana aos antibióticos convencionais.

The postoccidental deconstruction and resignification of "Modernity'': a critical analysis

The thesis which follows, entitled ''The Postoccidental Deconstruction and Resignification of 'Modemity': A Critical Analysis", is an exposition and criticism of the critique of occidental modemity found in a group of writings which identify their critique with a "postoccidental" point of view with respect to postcolonial studies. The general problem ofthe investigation concems the significance and reach ofthis critique of modemity in relation to the ongoing debate, in Latín American studies, about the historical relationship between Latín America, as a mu1ticultural/ structurally heterogeneous region, and the industrial societies of Euro pe and North America. A brief Preface explains the genealogy of the author's ideas on this subject Following this preface, the thesis proceeds to analyze the writings in this corpus through an intertextual, schematic approach which singles out two rnajor elements of the postoccidental critique: "coloniality" and "eurocentrism". These two main elements are investigated in the Introduction and Chapters One and Two, in terms of how they distinguish postoccidental analysis from other theoretical tendencias with which it has affinities but whose key concepts it reformu1ates in ways that are key to the unique approach which postoccidental analysis takes to modemity, the nature of the capitalist world system, colonialism, subaltemization, center/periphery and development . Chapter Three attempts a critical analysis of the foregoing postoccidentalist deconstruction according to the following question: to what extent does it succeed in deconstructing "modernity" as a term which refers to a historically articulated set of discourses whose underlying purpose has been to justify European and North American hegemony and structural asymmetries vis-a-vis the peripheries of the capitalist world system, based on an ethnocentric, racialist logic of exploitation and subalternization of non-European peoples? A Conclusion follows Chapter Three.