903 resultados para race-based discrimination


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Black boys are confronted with unique educational circumstances. They are often misdiagnosed and misplaced into special education programs (Bush-Daniels, 2008; Patton, 1998; Terman et al., 1996). Additionally, they are less likely to be enrolled in gifted and talented programs, even if their former achievements reflect their aptitude to succeed (Black Alliance for Educational Options, n.d.; Moore & Flowers, 2012). Given these statistics, a considerable emphasis has been placed on the causes and the consequences of low/under achievement for this population. As a result, the experiences of Black males who are achieving have been greatly neglected. Moreover, little is known about the factors that facilitate academic achievement among high-achieving Black boys. In an effort to bring the heterogenic nature of schooling experiences for Black boys to light, the present study examined the influence risk and protective factors had on the academic experiences of high-achieving Black boys. Grounded in the risk and resilience framework and the Integrative Model for the Study of Minority Youth Development, this study explored whether the high-achieving Black high school boys in this sample (n =88) reported experiencing discrimination (i.e. academic-based) and how this academic-based discrimination related to their 1) academic performance (i.e. GPA), 2) perceptions of math ability, and 3) race-based academic self-concept. In addition to exploring how academic-based discrimination was linked to academic achievement, this study examined how cultural resources such as racial socialization messages and racial identity related to academic achievement. Specifically, cultural socialization, preparation for bias, egalitarianism, private regard and public regard were evaluated alongside the three academic outcomes under study. Finally, the study explored whether aspects of racial socialization or racial identity buffered the effects of discrimination on any of the outcomes. Interestingly, the race/ethnicity of the student mattered for how students perceived their math ability. The risk factor academic-based discrimination was linked to academic performance. Cultural resources cultural socialization, preparation for bias, and private regard were linked to various academic outcomes of interest. There was only one significant moderating effect: a high private regard buffered the relationship between academic-based discrimination and race-based academic self-concept. Limitations and implications of this study are discussed.

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In this contribution, I am interested in how discrimination issues are manifested in employment relations in the United Nations (UN), a public forum to all states political leaders to advance their concerns, the World Bank, a financial organization that promotes economic development, mainly in developing countries, and the Consultative Group on International Agricultural Research (CGIAR), the eldest and largest global public program of the World Bank with a strategic network of diverse stakeholders that harnesses the best in science to produce more and better food, reduce poverty and sustain environments. Considering the immunity and privileges granted to international organizations, what are the current available legal procedures, at the national or international level, for workplace equality? How accountable and transparent are they, based on the practice of these organizations? Can discrimination biases that go beyond the known individual-based discrimination claims be identified? If so, how can they be challenged and changed? Based of the special position of international civil servants in international organizations and the duty to protect their fundamental rights, I claim that the limitation of opportunity by discriminatory biases and the psychic burden on the individual staff member, on daily basis, qualify for a workplace wrong and call for independent and impartial legal procedures that would ensure due process and fair treatment.

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Making Sense of Mass Education provides a comprehensive analysis of the field of mass education. The book presents new assessment of traditional issues associated with education – class, race, gender, discrimination and equity –to dispel myths and assumptions about the classroom. It examines the complex relationship between the media, popular culture and schooling, and places the expectations surrounding the modern teacher within ethical, legal and historical contexts. The book blurs some of the disciplinary boundaries within the field of education, drawing upon sociology, cultural studies, history, philosophy, ethics and jurisprudence to provide stronger analyses. The book reframes the sociology of education as a complex mosaic of cultural practices, forces and innovations. Engaging and contemporary, it is an invaluable resource for teacher education students, and anyone interested in a better understanding of mass education.

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1. The conservation status of the dingo Canis familiaris dingo is threatened by hybridization with the domestic dog C. familiaris familiaris. A practical method that can estimate the different levels of hybridization in the field is urgently required so that animals below a specific threshold of dingo ancestry (e.g. 1/4 or 1/2 dingoes) can reliably be identified and removed from dingo populations. 2. Skull morphology has been traditionally used to assess dingo purity, but this method does not discriminate between the different levels of dingo ancestry in hybrids. Furthermore, measurements can only be reliably taken from the skulls of dead animals. 3. Methods based on the analysis of variation in DNA are able to discriminate between the different levels of hybridization, but the validity of this method has been questioned because the materials currently used as a reference for dingoes are from captive animals of unproven genetic purity. The use of pre-European materials would improve the accuracy of this method, but suitable material has not been found in sufficient quantity to develop a reliable reference population. Furthermore, current methods based on DNA are impractical for the field-based discrimination of hybrids because samples require laboratory analysis. 4. Coat colour has also been used to estimate the extent of hybridization and is possibly the most practical method to apply in the field. However, this method may not be as powerful as genetic or morphological analyses because some hybrids (e.g. Australian cattle dog × dingo) are similar to dingoes in coat colour and body form. This problem may be alleviated by using additional visual characteristics such as the presence/absence of ticking and white markings.

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As investigações em torno da atuação política da imprensa costumam partir de duas posturas teóricas opostas. De um lado, alguns analistas enfatizam a importância da imprensa para a constituição de uma esfera pública nas democracias modernas. Desse prisma, ela seria encarregada de viabilizar o debate público e submeter ao escrutínio da sociedade as decisões estatais. Do outro lado, uma perspectiva mais cética defende que a imprensa não pode ser tomada como um pilar da esfera pública. Suas rotinas e estruturas a tornariam uma instância de manipulação retórica incompatível com o ideal moderno de um público deliberativo. Contudo, para além dessas oposições é importante notar que o ideal de uma deliberação pública mediada pela imprensa tem funcionado historicamente como um discurso de legitimação para a própria imprensa. Partindo da premissa de que a ideia de esfera pública é uma categoria política, esta pesquisa pretende entender de que modo alguns jornais se servem de uma dada concepção de esfera pública para se autolegitimarem enquanto pilares do debate público democrático. Através do estudo da maneira como a grande imprensa brasileira lidou com o tema das ações afirmativas raciais no ensino superior, este trabalho mostra como determinados enquadramentos midiáticos serviram para que a imprensa reivindicasse para si o status de esfera pública de debate do tema. A pesquisa se baseou numa análise de todos os textos sobre as ações afirmativas raciais no ensino superior publicados entre 2001 e 2009 nos dois principais jornais brasileiros: O Globo e Folha de S. Paulo. No total, 1.831 textos de diferentes tipos (reportagens, artigos, colunas, editoriais, cartas de leitores etc.) foram compilados e analisados a partir de Programas Computacionais de Codificação Assistida de Dados Qualitativos (CAQDAS, na sigla anglófona). A análise indica que ambos os jornais promoveram uma dramatização pública da controvérsia ao organizarem as discussões em torno das ações afirmativas raciais de acordo com determinados modelos de esfera pública. Tal dramatização não somente possibilitou que a imprensa influenciasse os destinos das ações afirmativas raciais no país, apresentando-as como medidas essencialmente polêmicas, mas também limitou a cobertura a estruturas narrativas padronizadas

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Heat shock protein 22 (HSP22) is an important member of small heat shock protein (sHSP) subfamily which plays a key role in the process of protecting cells, facilitating the folding of nascent peptides, and responding to stress. In the present study, the cDNA of HSP22 was cloned from Argopecten irradians (designated as AiHSP22) by rapid amplification cDNA end (RACE) based on the expressed sequence tags (ESTs). The full-length cDNA of AiHSP22 was of 1,112 bp, with an open reading frame of 588 bp encoding a polypeptide of 195 amino acids. The deduced amino acid sequence of AiHSP22 showed high similarity to previously identified HSP22s. The expression patterns of AiHSP22 mRNA in different tissues and in haemocytes of scallops exposed to Cd2+, Pb2+ or Cu2+ were investigated by real-time quantitative RT-PCR. The mRNA of AiHSP22 was constitutively expressed in all examined tissues, including haemocyte, muscle, kidney, gonad, gill and heart. The expression level in heart and muscle was higher than that in other tissues. The mRNA level of AiHSP22 in haemocytes was up-regulated after a 10 days exposure of scallops to Cu2+, Pb2+ and Cd2+. However, the expression of AiHSP22 did not increase linearly along with the rise of heavy metal concentration. Different concentrations of the same metal resulted in different effects on AiHSP22 expression. The sensitive response of AiHSP22 to Cu2+, Pb2+ and Cd2+ stress indicated that it could be developed as an indicator of exposure to heavy metals for the pollution monitoring programs in aquatic environment.

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Age-based discrimination in the supply of goods and services (including educational services) has only very recently been outlawed in the United Kingdom by the Equality Act 2010, the relevant sections of which have not yet been brought into force. This paper critically considers the Act and its implications, as well as the current proposal for an EU Directive on Goods and Services.The greatest immediate potential of the Equality Act lies in the general prohibition against age discrimination and the scope of the exceptions to it. The paper argues that exceptions permitting service providers to discriminate against older people (i.e. negative exceptions) should be very specifically set out in the reforming legislation.There should be no general defence to a claim of age discrimination based around the concept of ‘reasonableness’, which would not be consistently interpreted by courts and tribunals in a way that steers clear of traditional ageist assumptions and stereotyping.The paper argues that service providers should be permitted to discriminate in favour of older people (i.e. make positive exceptions) if the reason for doing do so satisfi es legislative criteria which are designed, amongst other things, to meet the particular needs of older persons or to promote social inclusion. Under this proposal, preferential treatment such as age-related concessionary fees for adult education courses and programmes would be lawful.

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Drawing on a growing literature on the interconnection of queer theory, sexuality and space, this thesis critically assesses the development, implementation and impact of a campus-based Positive Space Campaign aimed at raising the visibility and number of respectful, supportive, educational and welcoming spaces for lesbian, gay, bi, trans, two-spirited, queer and questioning (LGBTQ) students staff and faculty. The analysis, based on participatory action research (PAR), interrogates the extent to which the Positive Space Campaign challenges heteronormativity on campus. I contend that the Campaign, in its attempt to challenge dominant notions of sex, gender and sexuality, disrupts heterosexual space. Further, as I consider the meanings of 'queer', I consider the extent to which Positive Space Campaigns may be 'queering' space, by contributing to an 'imagined' campus space free of sexual and gender-based discrimination. The case study contributes to queer theory, the literature on sexuality and space, the literature on queer organizing in educational spaces and to broader queer organizing efforts in Canada.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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THE TITLE OF MY THESIS IS THE ROLE OF THE IDEAS AND THEIR CHANGE IN HIGHER EDUCATION POLICY-MAKING PROCESSES FROM THE EIGHTIES TO PRESENT-DAY: THE CASES OF ENGLAND AND NEW ZEALAND IN COMPARATIVE PERSPECTIVE UNDER A THEORETICAL POINT OF VIEW, THE AIM OF MY WORK IS TO CARRY OUT A RESEARCH MODELLED ON THE CONSTRUCTIVIST THEORY. IT FOCUSES ON THE ANALYSIS OF THE IMPACT OF IDEAS ON THE PROCESSES OF POLICY MAKING BY MEANS OF EPISTEMIC COMMUNITIES, THINK TANKS AND VARIOUS SOCIOECONOMIC CONTEXTS THAT MAY HAVE PLAYED A KEY ROLE IN THE CONSTRUCTION OF THE DIFFERENT PATHS. FROM MY POINT OF VIEW IDEAS CONSTITUTE A PRIORITY RESEARCH FIELD WHICH IS WORTH ANALYSING SINCE THEIR ROLE IN POLICY MAKING PROCESSES HAS BEEN TRADITIONALLY RATHER UNEXPLORED. IN THIS CONTEXT AND WITH THE AIM OF DEVELOPING A RESEARCH STRAND BASED ON THE ROLE OF IDEAS, I INTEND TO CARRY ON MY STUDY UNDER THE PERSPECTIVE OF CHANGE. DEPENDING ON THE DATA AND INFORMATION THAT I COLLECTED I EVALUATED THE WEIGHT OF EACH OF THESE VARIABLES AND MAYBE OTHERS SUCH AS THE INSTITUTIONS AND THE INDIVIDUAL INTERESTS, WHICH MAY HAVE INFLUENCED THE FORMATION OF THE POLICY MAKING PROCESSES. UNDER THIS LIGHT, I PLANNED TO ADOPT THE QUALITATIVE METHODOLOGY OF RESEARCH WHICH I BELIEVE TO BE VERY EFFECTIVE AGAINST THE MORE DIFFICULT AND POSSIBLY REDUCTIVE APPLICATION OF QUANTITIVE DATA SETS. I RECKON THEREFORE THAT THE MOST APPROPRIATE TOOLS FOR INFORMATION PROCESSING INCLUDE CONTENT ANALYSIS, AND IN-DEPTH INTERVIEWS TO PERSONALITIES OF THE POLITICAL PANORAMA (ÉLITE OR NOT) WHO HAVE PARTICIPATED IN THE PROCESS OF HIGHER EDUCATION REFORM FROM THE EIGHTIES TO PRESENT-DAY. THE TWO CASES TAKEN INTO CONSIDERATION SURELY SET AN EXAMPLE OF RADICAL REFORM PROCESSES WHICH HAVE OCCURRED IN QUITE DIFFERENT CONTEXTS DETERMINED BY THE SOCIOECONOMIC CHARACTERISTICS AND THE TRAITS OF THE ÉLITE. IN NEW ZEALAND THE DESCRIBED PROCESS HAS TAKEN PLACE WITH A STEADY PACE AND A GOOD GRADE OF CONSEQUANTIALITY, IN LINE WTH THE REFORMS IN OTHER STATE DIVISIONS DRIVEN BY THE IDEAS OF THE NEW PUBLIC MANAGEMENT. CONTRARILY IN ENGLAND THE REFORMATIVE ACTION OF MARGARET THATCHER HAS ACQUIRED A VERY RADICAL CONNOTATION AS IT HAS BROUGHT INTO THE AMBIT OF HIGHER EDUCATION POLICY CONCEPTS LIKE EFFICIENCY, EXCELLENCE, RATIONALIZATION THAT WOULD CONTRAST WITH THE GENERALISTIC AND MASS-ORIENTED IDEAS THAT WERE FASHIONABLE DURING THE SEVENTIES. THE MISSION I INTEND TO ACCOMPLISH THORUGHOUT MY RESEARCH IS TO INVESTIGATE AND ANALYSE INTO MORE DEPTH THE DIFFERENCES THAT SEEM TO EMERGE FROM TWO CONTEXTS WHICH MOST OF THE LITERATURE REGARDS AS A SINGLE MODEL: THE ANGLO-SAXON MODEL. UNDER THIS LIGHT, THE DENSE ANALYSIS OF POLICY PROCESSES ALLOWED TO BRING OUT BOTH THE CONTROVERSIAL AND CONTRASTING ASPECTS OF THE TWO REALITIES COMPARED, AND THE ROLE AND WEIGHT OF VARIABLES SUCH AS IDEAS (MAIN VARIABLE), INSTITUTIONAL SETTINGS AND INDIVIDUAL INTERESTS ACTING IN EACH CONTEXT. THE CASES I MEAN TO ATTEND PRESENT PECULIAR ASPECTS WORTH DEVELOPING AN IN-DEPTH ANALYSIS, AN OUTLINE OF WHICH WILL BE PROVIDED IN THIS ABSTRACT. ENGLAND THE CONSERVATIVE GOVERNMENT, SINCE 1981, INTRODUCED RADICAL CHANGES IN THE SECTOR OF HIGHER EDUCATION: FIRST CUTTING DOWN ON STATE FUNDINGS AND THEN WITH THE CREATION OF AN INSTITUTION FOR THE PLANNING AND LEADERSHIP OF THE POLYTECHNICS (NON-UNIVERSITY SECTOR). AFTERWARDS THE SCHOOL REFORM BY MARGARET THATCHER IN 1988 RAISED TO A GREAT STIR ALL OVER EUROPE DUE TO BOTH ITS CONSIDERABLE INNOVATIVE IMPRINT AND THE STRONG ATTACK AGAINST THE PEDAGOGY OF THE ‘ACTIVE’ SCHOOLING AND PROGRESSIVE EDUCATION, UNTIL THEN RECOGNIZED AS A MERIT OF THE BRITISH PUBLIC SCHOOL. IN THE AMBIT OF UNIVERSITY EDUCATION THIS REFORM, TOGETHER WITH SIMILAR MEASURES BROUGHT IN DURING 1992, PUT INTO PRACTICE THE CONSERVATIVE PRINCIPLES THROUGH A SERIES OF ACTIONS THAT INCLUDED: THE SUPPRESSION OF THE IRREMOVABILITY PRINCIPLE FOR UNIVERSITY TEACHERS; THE INTRODUCTION OF STUDENT LOANS FOR LOW-INCOME STUDENTS AND THE CANCELLATION OF THE CLEAR DISTINCTION BETWEEN UNIVERSITIES AND POLYTECHNICS. THE POLICIES OF THE LABOUR MAJORITY OF MR BLAIR DID NOT QUITE DIVERGE FROM THE CONSERVATIVES’ POSITION. IN 2003 BLAIR’S CABINET RISKED TO BECOME A MINORITY RIGHT ON THE OCCASION OF AN IMPORTANT UNIVERSITY REFORM PROPOSAL. THIS PROPOSAL WOULD FORESEE THE AUTONOMY FOR THE UNIVERSITIES TO RAISE UP TO 3.000 POUNDS THE ENROLMENT FEES FOR STUDENTS (WHILE FORMERLY THE CEILING WAS 1.125 POUNDS). BLAIR HAD TO FACE INTERNAL OPPOSITION WITHIN HIS OWN PARTY IN RELATION TO A MEASURE THAT, ACCORDING TO THE 150 MPS PROMOTERS OF AN ADVERSE MOTION, HAD NOT BEEN INCLUDED IN THE ELECTORAL PROGRAMME AND WOULD RISK CREATING INCOME-BASED DISCRIMINATION AMONG STUDENTS. AS A MATTER OF FACT THE BILL FOCUSED ON THE INTRODUCTION OF VERY LOW-INTEREST STUDENT LOANS TO BE SETTLED ONLY WHEN THE STUDENT WOULD HAVE FOUND A REMUNERATED OCCUPATION (A SYSTEM ALREADY PROVIDED FOR BY THE AUSTRALIAN LEGISLATION). NEW ZEALAND CONTRARILY TO MANY OTHER COUNTRIES, NEW ZEALAND HAS ADOPTED A VERY WIDE VISION OF THE TERTIARY EDUCATION. IT INCLUDES IN FACT THE FULL EDUCATIONAL PROGRAMME THAT IS INTERNATIONALLY RECOGNIZED AS THE POST-SECONDARY EDUCATION. SHOULD WE SPOTLIGHT A PECULIARITY OF THE NEW ZEALAND TERTIARY EDUCATION POLICY THEN IT WOULD BE ‘CHANGE’. LOOKING AT THE REFORM HISTORY RELATED TO THE TERTIARY EDUCATION SYSTEM, WE CAN CLEARLY IDENTIFY FOUR ‘SUB-PERIODS’ FROM THE EIGHTIES TO PRESENT-DAY: 1. BEFORE THE 80S’: AN ELITARIAN SYSTEM CHARACTERIZED BY LOW PARTICIPATION RATES. 2. BETWEEN MID AND LATE 80S’: A TREND TOWARDS THE ENLARGEMENT OF PARTICIPATION ASSOCIATED TO A GREATER COMPETITION. 3. 1990-1999: A FUTHER STEP TOWARDS A COMPETITIVE MODEL BASED ON THE MARKET-ORIENTED SYSTEM. 4. FROM 2000 TO TODAY: A CONTINUOUS EVOLUTION TOWARDS A MORE COMPETITIVE MODEL BASED ON THE MARKET-ORIENTED SYSTEM TOGETHER WITH A GROWING ATTENTION TO STATE CONTROL FOR SOCIAL AND ECONOMIC DEVELOPMENT OF THE NATION. AT PRESENT THE GOVERNMENT OF NEW ZEALAND OPERATES TO STRENGHTHEN THIS PROCESS, PRIMARILY IN RELATION TO THE ROLE OF TERTIARY EDUCATION AS A STEADY FACTOR OF NATIONAL WALFARE, WHERE PROFESSIONAL DEVELOPMENT CONTRIBUTES ACTIVELY TO THE GROWTH OF THE NATIONAL ECONOMIC SYSTEM5. THE CASES OF ENGLAND AND NEW ZEALAND ARE THE FOCUS OF AN IN-DEPTH INVESTIGATION THAT STARTS FROM AN ANALYSIS OF THE POLICIES OF EACH NATION AND DEVELOP INTO A COMPARATIVE STUDY. AT THIS POINT I ATTEMPT TO DRAW SOME PRELIMINARY IMPRESSIONS ON THE FACTS ESSENTIALLY DECRIBED ABOVE. THE UNIVERSITY POLICIES IN ENGLAND AND NEW ZEALAND HAVE BOTH UNDERGONE A SIGNIFICANT REFORMATORY PROCESS SINCE THE EARLY EIGHTIES; IN BOTH CONTEXTS THE IMPORTANCE OF IDEAS THAT CONSTITUTED THE BASE OF POLITICS UNTIL 1980 WAS QUITE RELEVANT. GENERALLY SPEAKING, IN BOTH CASES THE PRE-REFORM POLICIES WERE INSPIRED BY EGALITARIANISM AND EXPANSION OF THE STUDENT POPULATION WHILE THOSE BROUGHT IN BY THE REFORM WOULD PURSUE EFFICIENCY, QUALITY AND COMPETITIVENESS. UNDOUBTEDLY, IN LINE WITH THIS GENERAL TENDENCY THAT REFLECTS THE HYPOTHESIS PROPOSED, THE TWO UNIVERSITY SYSTEMS PRESENT SEVERAL DIFFERENCES. THE UNIVERSITY SYSTEM IN NEW ZEALAND PROCEEDED STEADILY TOWARDS THE IMPLEMENTATION OF A MANAGERIAL CONCEPTION OF TERTIARY EDUCATION, ESPECIALLY FROM 1996 ONWARDS, IN ACCORDANCE WITH THE REFORMATORY PROCESS OF THE WHOLE PUBLIC SECTOR. IN THE UNITED KINGDOM, AS IN THE REST OF EUROPE, THE NEW APPROACH TO UNIVERSITY POLICY-MAKING HAD TO CONFRONT A DEEP-ROOTED TRADITION OF PROGRESSIVE EDUCATION AND THE IDEA OF EDUCATION EXPANSION THAT IN FACT DOMINATED UNTIL THE EIGHTIES. FROM THIS VIEW POINT THE GOVERNING ACTION OF MARGARET THATCHER GAVE RISE TO A RADICAL CHANGE THAT REVOLUTIONIZED THE OBJECTIVES AND KEY VALUES OF THE WHOLE EDUCATIONAL SYSTEM, IN PARTICULAR IN THE HIGHER EDUCATION SECTOR. IDEAS AS EFFICIENCY, EXCELLENCE AND CONTROL OF THE PERFORMANCE BECAME DECISIVE. THE LABOUR CABINETS OF BLAIR DEVELOPED IN THE WAKE OF CONSERVATIVE REFORMS. THIS APPEARS TO BE A FOCAL POINT OF THIS STUDY THAT OBSERVES HOW ALSO IN NEW ZEALAND THE REFORMING PROCESS OCCURRED TRANSVERSELY DURING PROGRESSIVE AND CONSERVATIVE ADMINISTRATIONS. THE PRELIMINARY IMPRESSION IS THEREFORE THAT IDEAS DEEPLY MARK THE REFORMATIVE PROCESSES: THE AIM OF MY RESEARCH IS TO VERIFY TO WHICH EXTENT THIS STATEMENT IS TRUE. IN ORDER TO BUILD A COMPREHENSIVE ANALYLIS, FURTHER SIGNIFICANT FACTORS WILL HAVE TO BE INVESTIGATED: THE WAY IDEAS ARE PERCEIVED AND IMPLEMENTED BY THE DIFFERENT POLITICAL ELITES; HOW THE VARIOUS SOCIOECONOMIC CONTEXTS INFLUENCE THE REFORMATIVE PROCESS; HOW THE INSTITUTIONAL STRUCTURES CONDITION THE POLICY-MAKING PROCESSES; WHETHER INDIVIDUAL INTERESTS PLAY A ROLE AND, IF YES, TO WHICH EXTENT.

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The genus Campylobacter comprises 17 species, some of which are important animal and human pathogens. To gain more insight into the genetic relatedness of this genus and to improve the molecular tools available for diagnosis, a universal sequencing approach was established for the gene encoding the beta-subunit of RNA polymerase (rpoB) for the genus Campylobacter. A total of 59 strains, including the type strains of currently recognized species as well as field isolates, were investigated in the study. A primer set specific for Campylobacter species enabled straightforward amplification and sequencing of a 530 bp fragment of the rpoB gene. The 16S rRNA gene sequences of all of the strains were determined in parallel. A good congruence was obtained between 16S rRNA and rpoB gene sequence-based trees within the genus Campylobacter. The branching of the rpoB tree was similar to that of the 16S rRNA gene tree, even though a few discrepancies were observed for certain species. The resolution of the rpoB gene within the genus Campylobacter was generally much higher than that of the 16S rRNA gene sequence, resulting in a clear separation of most species and even some subspecies. The universally applicable amplification and sequencing approach for partial rpoB gene sequence determination provides a powerful tool for DNA sequence-based discrimination of Campylobacter species.

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1. The conservation status of the dingo Canis familiaris dingo is threatened by hybridization with the domestic dog C. familiaris familiaris. A practical method that can estimate the different levels of hybridization in the field is urgently required so that animals below a specific threshold of dingo ancestry (e.g. 1/4 or 1/2 dingoes) can reliably be identified and removed from dingo populations. 2. Skull morphology has been traditionally used to assess dingo purity, but this method does not discriminate between the different levels of dingo ancestry in hybrids. Furthermore, measurements can only be reliably taken from the skulls of dead animals. 3. Methods based on the analysis of variation in DNA are able to discriminate between the different levels of hybridization, but the validity of this method has been questioned because the materials currently used as a reference for dingoes are from captive animals of unproven genetic purity. The use of pre-European materials would improve the accuracy of this method, but suitable material has not been found in sufficient quantity to develop a reliable reference population. Furthermore, current methods based on DNA are impractical for the field-based discrimination of hybrids because samples require laboratory analysis. 4. Coat colour has also been used to estimate the extent of hybridization and is possibly the most practical method to apply in the field. However, this method may not be as powerful as genetic or morphological analyses because some hybrids (e.g. Australian cattle dog x dingo) are similar to dingoes in coat colour and body form. This problem may be alleviated by using additional visual characteristics such as the presence/absence of ticking and white markings.

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We develop a multi-agent based model to simulate a population which comprises of two ethnic groups and a peacekeeping force. We investigate the effects of different strategies for civilian movement to the resulting violence in this bi-communal population. Specifically, we compare and contrast random and race-based migration strategies. Race-based migration leads the formation of clusters. Previous work in this area has shown that same-race clustering instigates violent behavior in otherwise passive segments of the population. Our findings confirm this. Furthermore, we show that in settings where only one of the two races adopts race-based migration it is a winning strategy especially in violently predisposed populations. On the other hand, in relatively peaceful settings clustering is a restricting factor which causes the race that adopts it to drift into annihilation. Finally, we show that when race-based migration is adopted as a strategy by both ethnic groups it results in peaceful co-existence even in the most violently predisposed populations.

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Integrating information from multiple sources is a crucial function of the brain. Examples of such integration include multiple stimuli of different modalties, such as visual and auditory, multiple stimuli of the same modality, such as auditory and auditory, and integrating stimuli from the sensory organs (i.e. ears) with stimuli delivered from brain-machine interfaces.

The overall aim of this body of work is to empirically examine stimulus integration in these three domains to inform our broader understanding of how and when the brain combines information from multiple sources.

First, I examine visually-guided auditory, a problem with implications for the general problem in learning of how the brain determines what lesson to learn (and what lessons not to learn). For example, sound localization is a behavior that is partially learned with the aid of vision. This process requires correctly matching a visual location to that of a sound. This is an intrinsically circular problem when sound location is itself uncertain and the visual scene is rife with possible visual matches. Here, we develop a simple paradigm using visual guidance of sound localization to gain insight into how the brain confronts this type of circularity. We tested two competing hypotheses. 1: The brain guides sound location learning based on the synchrony or simultaneity of auditory-visual stimuli, potentially involving a Hebbian associative mechanism. 2: The brain uses a ‘guess and check’ heuristic in which visual feedback that is obtained after an eye movement to a sound alters future performance, perhaps by recruiting the brain’s reward-related circuitry. We assessed the effects of exposure to visual stimuli spatially mismatched from sounds on performance of an interleaved auditory-only saccade task. We found that when humans and monkeys were provided the visual stimulus asynchronously with the sound but as feedback to an auditory-guided saccade, they shifted their subsequent auditory-only performance toward the direction of the visual cue by 1.3-1.7 degrees, or 22-28% of the original 6 degree visual-auditory mismatch. In contrast when the visual stimulus was presented synchronously with the sound but extinguished too quickly to provide this feedback, there was little change in subsequent auditory-only performance. Our results suggest that the outcome of our own actions is vital to localizing sounds correctly. Contrary to previous expectations, visual calibration of auditory space does not appear to require visual-auditory associations based on synchrony/simultaneity.

My next line of research examines how electrical stimulation of the inferior colliculus influences perception of sounds in a nonhuman primate. The central nucleus of the inferior colliculus is the major ascending relay of auditory information before it reaches the forebrain, and thus an ideal target for understanding low-level information processing prior to the forebrain, as almost all auditory signals pass through the central nucleus of the inferior colliculus before reaching the forebrain. Thus, the inferior colliculus is the ideal structure to examine to understand the format of the inputs into the forebrain and, by extension, the processing of auditory scenes that occurs in the brainstem. Therefore, the inferior colliculus was an attractive target for understanding stimulus integration in the ascending auditory pathway.

Moreover, understanding the relationship between the auditory selectivity of neurons and their contribution to perception is critical to the design of effective auditory brain prosthetics. These prosthetics seek to mimic natural activity patterns to achieve desired perceptual outcomes. We measured the contribution of inferior colliculus (IC) sites to perception using combined recording and electrical stimulation. Monkeys performed a frequency-based discrimination task, reporting whether a probe sound was higher or lower in frequency than a reference sound. Stimulation pulses were paired with the probe sound on 50% of trials (0.5-80 µA, 100-300 Hz, n=172 IC locations in 3 rhesus monkeys). Electrical stimulation tended to bias the animals’ judgments in a fashion that was coarsely but significantly correlated with the best frequency of the stimulation site in comparison to the reference frequency employed in the task. Although there was considerable variability in the effects of stimulation (including impairments in performance and shifts in performance away from the direction predicted based on the site’s response properties), the results indicate that stimulation of the IC can evoke percepts correlated with the frequency tuning properties of the IC. Consistent with the implications of recent human studies, the main avenue for improvement for the auditory midbrain implant suggested by our findings is to increase the number and spatial extent of electrodes, to increase the size of the region that can be electrically activated and provide a greater range of evoked percepts.

My next line of research employs a frequency-tagging approach to examine the extent to which multiple sound sources are combined (or segregated) in the nonhuman primate inferior colliculus. In the single-sound case, most inferior colliculus neurons respond and entrain to sounds in a very broad region of space, and many are entirely spatially insensitive, so it is unknown how the neurons will respond to a situation with more than one sound. I use multiple AM stimuli of different frequencies, which the inferior colliculus represents using a spike timing code. This allows me to measure spike timing in the inferior colliculus to determine which sound source is responsible for neural activity in an auditory scene containing multiple sounds. Using this approach, I find that the same neurons that are tuned to broad regions of space in the single sound condition become dramatically more selective in the dual sound condition, preferentially entraining spikes to stimuli from a smaller region of space. I will examine the possibility that there may be a conceptual linkage between this finding and the finding of receptive field shifts in the visual system.

In chapter 5, I will comment on these findings more generally, compare them to existing theoretical models, and discuss what these results tell us about processing in the central nervous system in a multi-stimulus situation. My results suggest that the brain is flexible in its processing and can adapt its integration schema to fit the available cues and the demands of the task.

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La principal finalidad de este estudio, es presentar una visión actualizada y genérica respecto a las condicionantes económicas de Colombia en particular y las relacionadas con el conjunto de países que conforman la Alianza del Pacífico en general –Chile, Colombia, México y Perú. Se trata de un estudio no experimental, descriptivo-interpretativo con énfasis en la revisión de datos. Entre las conclusiones más importantes se destacan los niveles de crecimiento económico con mayor estabilidad se presentan en Chile y Perú, una dependencia comercial exterior de México hacia Estados Unidos y que en Colombia se tiene el caso de que el aumento de producción que se hace evidente, no impacta tanto como era de esperarse, en la variable empleo.