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Parental investment across an altitudinal gradient in blue tits (Cyanistes caeruleus)Bruendl, Aisha Colleen January 2017 (has links)
Environmental gradients can help shed light on the evolution of life history strategies such as parental investment. Parental investment is crucial for the fitness of many species. In this thesis, I examine reproductive investment dynamics in the Eurasian blue tit (Cyanistes caeruleus) in the French Pyrenees and assess potential differences in reproductive measures across an altitudinal gradient that creates variation in environmental “harshness”. Further, I investigate fine-scale aspects of bi-parental care, such as investment tactics in current reproduction, and sex differences in contributions to offspring care. To do so, I used a mixture of observational and experimental data, collected over a total of six breeding seasons from over 500 blue tits nests. I showed that breeding conditions are “harsher” due to colder temperatures with increasing elevation, leading to changes in reproductive timing and output. I found that increasing altitude leads to decreased hatching success. Nevertheless, clutch size and brood mortality is comparable across the gradient. A shift to a lower, but qualitatively comparable reproductive output may be part of a slower “pace of life” strategies pursued at high relative to low altitudes. From experimental data, I also found that parental investment is positively linked across different phases within one reproductive attempt. Finally, in line with theory, a temporary brood manipulation revealed that parents balance the benefits and costs of reproduction by partially compensating for changes in brood size. Parents also responded in similar ways to brood size. Overall, the findings presented in this thesis highlight the importance of mechanisms to fine-tune reproduction to maximise reproductive fitness. I suggest that initial reproductive decisions such as timing and amount of offspring produced heavily shape the success of a reproductive attempt. These results have implications for current versus future reproductive trade-offs in life history theory, in particular for short-lived species.
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Essays on effects of uncertainty on competition among firms and political partiesBrzezinski, Krzysztof January 2017 (has links)
This thesis investigates different aspects of competition under uncertainty using the tools of game theory. In Chapter 1, I consider a quantity oligopoly game. One of the firms is presented with an opportunity to commit to some output before the demand becomes known, but may add to it afterwards, then moving simultaneously with the rivals. I show that the more cost-efficient firm is more likely to behave like a Stackelberg leader, i.e. to produce the optimal Stackelberg leader quantity ex-ante and refrain from adding to it later, letting the rivals respond to its ex-ante output in the manner of Stackelberg followers. In Chapter 2, I study a model of an electoral contest. Two symmetric parties allocate their endowments to building platforms on various issues before the start of a campaign. Next, one of the issues becomes decisive in the course of the campaign with a commonly known probability. The outcome of the election depends on the difference in competence in this issue. I show that if the payoff functions are convex in this difference-the case of 'increasing returns to power'-parties differentiate each other by selecting different campaign issues. On the contrary, when the payoff functions are concave in this difference-the case of 'decreasing returns to power'-parties mimic each other by investing the same amounts into the same issues. Thus, incentives for selecting campaign issues depend critically on the shape of the payoff functions, which might be determined by (1) a non-linear technology transforming parties' investment in various topics into voters' perception of their competence, (2) or parties' inherent motivation for winning by a big margin due to parties' ideological convictions or rent-seeking, (3) or an electoral system giving winners or big parties a disproportionate advantage in the assigned number of seats, (4) or a relatively high extent of power given to the winning party once in office.
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Nitrogênio na semeadura e em cobertura para o feijoeiro em sistema plantio direto em fase de implantação e consolidadoPerez, Adelson Antonio Guidolin [UNESP] 13 August 2010 (has links) (PDF)
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perez_aag_me_botfca.pdf: 424626 bytes, checksum: 9357eb89f716f0e2a85803363cfbbb06 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Com o aumento do cultivo de feijão no sistema plantio direto, torna-se necessário o conhecimento da reposta dessa cultura ao nitrogênio em solo sem preparo convencional por diferentes períodos de tempo, já que a disponibilidade desse nutriente pode ser alterada pelo sistema de manejo do solo. O objetivo foi avaliar o efeito da aplicação antecipada e/ou em cobertura do nitrogênio no feijoeiro cultivado em áreas com sistema plantio direto recém-implantado ou consolidado. O experimento foi conduzido durante o período “da seca”, nos anos agrícolas 2007/08 e 2008/09, em um Nitossolo Vermelho, no município de Botucatu-SP. O delineamento experimental utilizado foi o de blocos casualizados em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram representadas por quatro sistemas de manejo (SPDR: sistema plantio direto recém-implantado (a cultura do feijão será a primeira cultura a ser implantada no sistema de plantio direto); SPDC: sistema plantio direto consolidado (23 anos após a implantação); SPDR+N: sistema plantio direto recém-implantado com aplicação de 60 kg ha-1 de nitrogênio antecipado; SPDC+N: sistema plantio direto consolidado com aplicação de 60 kg ha-1 de nitrogênio antecipado). As subparcelas foram constituídas por quatro doses de nitrogênio em cobertura (0, 30, 60 e 120 kg ha-1). A adubação de cobertura foi efetuada no estádio fenológico V4, nos dois anos agrícolas. O tempo que a área permaneceu sob sistema plantio direto não influenciou a resposta do feijoeiro à adubação nitrogenada. A antecipação do N contribuiu para a manutenção da população de plantas almejada. A aplicação de N antecipado e em cobertura aumentou o número de vagens por planta, a massa dos grãos, o teor de proteína nos grãos e a produtividade de grãos do feijoeiro.Houve maior eficiência de uso do N quando este foi antecipado, do que quando... / With the increase in common bean growth under no-tillage, it is necessary to know the response of this crop to nitrogen in soil without conventional tillage for different periods of time, since the availability of this nutrient can changed by the system of soil management. The aim of this study was to evaluate the effect of nitrogen early and/or sidedressed application for common bean crop, grown in newly implemented and established no-tillage system. The experiment was conducted during the dry period, in the 2007/08 and 2008/09 cropping seasons, on a Red Nitosol (Alfisol) located in Botucatu County, São Paulo State, Brazil. A randomized complete block design, in split-plot scheme, and four replications was used. The plots were composed by four management systems (NNT: newly implemented no-tillage system (common bean crop was the first to be cropped in no-tillage system); ENT: established no-tillage system (23 years without soil tillage); NNT+N: newly implemented notillage system with application of 60 kg ha-1 of nitrogen early at common bean sowing, and ENT+N established no-tillage system with application of 60 kg ha-1 of nitrogen early at common bean sowing). The subplots were composed by four sidedressed nitrogen doses (0, 30, 60, and 120 kg ha-1). The nitrogen sidedressing fertilization was performed in the V4 growth stage, in both cropping seasons. The time that area remained under no-tillage system did not influence the response of common bean plants to nitrogen fertilization. Nitrogen early application at common bean sowing contributed to maintaining the desired plant population. Nitrogen early and sidedressing application increased pods number per plant, grains weight,protein concentration in grains and grain yield of common bean. Nitrogen early application was more efficient than sidedressing application
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A 1.0 [mu]m CMOS all-digital clock multiplier.January 1997 (has links)
by Cheng King Sum Frankie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaf 53). / Acknowledgments --- p.iv / List of Figures --- p.vii / List of Tables --- p.ix / Abstract --- p.x / Chapter Chapter1 --- Introduction --- p.1 / Chapter 1.1 --- Multiple Clock System --- p.1 / Chapter 1.2 --- Clock Multiplier --- p.2 / Phase-Locked Loop --- p.2 / Delay Locked Loop --- p.3 / Chapter 1.3 --- Objective --- p.5 / Chapter Chapter2 --- All-Digital Clock Multiplier --- p.6 / Chapter 2.1 --- Architecture --- p.6 / Chapter 2.2 --- Operation --- p.7 / Chapter 2.3 --- Implementation --- p.9 / Control Circuit --- p.9 / Phase-Locked Circuit --- p.11 / Frequency Detector --- p.12 / Frequency Divider --- p.13 / Synchronize Logic --- p.14 / DCO Control --- p.15 / Chapter Chapter3 --- Digitally-Controlled Oscillator --- p.16 / Chapter 3.1 --- Principle --- p.16 / Chapter 3.2 --- Design --- p.18 / Transient Analysis --- p.18 / Simulation result --- p.26 / Chapter 3.3 --- Layout --- p.30 / Chapter 3.4 --- Summary --- p.32 / Chapter Chapter4 --- Test and Measurement --- p.34 / Chapter 4.1 --- Digitally-Controlled Oscillator Characteristics --- p.34 / Chapter 4.2 --- All-Digital Clock Multiplier Characteristics --- p.43 / Chapter Chapter5 --- Conclusions --- p.51 / Chapter 5.1 --- Summary --- p.51 / Chapter 5.2 --- Recommendation for Future Work --- p.52 / References --- p.53 / Appendix A --- p.54 / Publications and Presentations --- p.54
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An ICT image processing chip based on fast computation algorithm and self-timed circuit technique.January 1997 (has links)
by Johnson, Tin-Chak Pang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references. / Acknowledgments / Abstract / List of figures / List of tables / Chapter 1. --- Introduction --- p.1-1 / Chapter 1.1 --- Introduction --- p.1-1 / Chapter 1.2 --- Introduction to asynchronous system --- p.1-5 / Chapter 1.2.1 --- Motivation --- p.1-5 / Chapter 1.2.2 --- Hazards --- p.1-7 / Chapter 1.2.3 --- Classes of Asynchronous circuits --- p.1-8 / Chapter 1.3 --- Introduction to Transform Coding --- p.1-9 / Chapter 1.4 --- Organization of the Thesis --- p.1-16 / Chapter 2. --- Asynchronous Design Methodologies --- p.2-1 / Chapter 2.1 --- Introduction --- p.2-1 / Chapter 2.2 --- Self-timed system --- p.2-2 / Chapter 2.3 --- DCVSL Methodology --- p.2-4 / Chapter 2.3.1 --- DCVSL gate --- p.2-5 / Chapter 2.3.2 --- Handshake Control --- p.2-7 / Chapter 2.4 --- Micropipeline Methodology --- p.2-11 / Chapter 2.4.1 --- Summary of previous design --- p.2-12 / Chapter 2.4.2 --- New Micropipeline structure and improvements --- p.2-17 / Chapter 2.4.2.1 --- Asymmetrical delay --- p.2-20 / Chapter 2.4.2.2 --- Variable Delay and Delay Value Selection --- p.2-22 / Chapter 2.5 --- Comparison between DCVSL and Micropipeline --- p.2-25 / Chapter 3. --- Self-timed Multipliers --- p.3-1 / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.2 --- Design Example 1 : Bit-serial matrix multiplier --- p.3-3 / Chapter 3.2.1 --- DCVSL design --- p.3-4 / Chapter 3.2.2 --- Micropipeline design --- p.3-4 / Chapter 3.2.3 --- The first test chip --- p.3-5 / Chapter 3.2.4 --- Second test chip --- p.3-7 / Chapter 3.3 --- Design Example 2 - Modified Booth's Multiplier --- p.3-9 / Chapter 3.3.1 --- Circuit Design --- p.3-10 / Chapter 3.3.2 --- Simulation result --- p.3-12 / Chapter 3.3.3 --- The third test chip --- p.3-14 / Chapter 4. --- Current-Sensing Completion Detection --- p.4-1 / Chapter 4.1 --- Introduction --- p.4-1 / Chapter 4.2 --- Current-sensor --- p.4-2 / Chapter 4.2.1 --- Constant current source --- p.4-2 / Chapter 4.2.2 --- Current mirror --- p.4-4 / Chapter 4.2.3 --- Current comparator --- p.4-5 / Chapter 4.3 --- Self-timed logic using CSCD --- p.4-9 / Chapter 4.4 --- CSCD test chips and testing results --- p.4-10 / Chapter 4.4.1 --- Test result --- p.4-11 / Chapter 5. --- Self-timed ICT processor architecture --- p.5-1 / Chapter 5.1 --- Introduction --- p.5-1 / Chapter 5.2 --- Comparison of different architecture --- p.5-3 / Chapter 5.2.1 --- General purpose Digital Signal Processor --- p.5-5 / Chapter 5.2.1.1 --- Hardware and speed estimation : --- p.5-6 / Chapter 5.2.2 --- Micropipeline without fast algorithm --- p.5-7 / Chapter 5.2.2.1 --- Hardware and speed estimation : --- p.5-8 / Chapter 5.2.3 --- Micropipeline with fast algorithm (I) --- p.5-8 / Chapter 5.2.3.1 --- Hardware and speed estimation : --- p.5-9 / Chapter 5.2.4 --- Micropipeline with fast algorithm (II) --- p.5-10 / Chapter 5.2.4.1 --- Hardware and speed estimation : --- p.5-11 / Chapter 6. --- Implementation of self-timed ICT processor --- p.6-1 / Chapter 6.1 --- Introduction --- p.6-1 / Chapter 6.2 --- Implementation of Self-timed 2-D ICT processor (First version) --- p.6-3 / Chapter 6.2.1 --- 1-D ICT module --- p.6-4 / Chapter 6.2.2 --- Self-timed Transpose memory --- p.6-5 / Chapter 6.2.3 --- Layout Design --- p.6-8 / Chapter 6.3 --- Implementation of Self-timed 1-D ICT processor with fast algorithm (final version) --- p.6-9 / Chapter 6.3.1 --- I/O buffers and control units --- p.6-10 / Chapter 6.3.1.1 --- Input control --- p.6-11 / Chapter 6.3.1.2 --- Output control --- p.6-12 / Chapter 6.3.1.2.1 --- Self-timed Computational Block --- p.6-13 / Chapter 6.3.1.3 --- Handshake Control Unit --- p.6-14 / Chapter 6.3.1.4 --- Integer Execution Unit (IEU) --- p.6-18 / Chapter 6.3.1.5 --- Program memory and Instruction decoder --- p.6-20 / Chapter 6.3.2 --- Layout Design --- p.6-21 / Chapter 6.4 --- Specifications of the final version self-timed ICT chip --- p.6-22 / Chapter 7. --- Testing of Self-timed ICT processor --- p.7-1 / Chapter 7.1 --- Introduction --- p.7-1 / Chapter 7.2 --- Pin assignment of Self-timed 1 -D ICT chip --- p.7-2 / Chapter 7.3 --- Simulation --- p.7-3 / Chapter 7.4 --- Testing of Self-timed 1-D ICT processor --- p.7-5 / Chapter 7.4.1 --- Functional test --- p.7-5 / Chapter 7.4.1.1 --- Testing environment and results --- p.7-5 / Chapter 7.4.2 --- Transient Characteristics --- p.7-7 / Chapter 7.4.3 --- Comments on speed and power --- p.7-10 / Chapter 7.4.4 --- Determination of optimum delay control voltage --- p.7-12 / Chapter 7.5 --- Testing of delay element and other logic cells --- p.7-13 / Chapter 8. --- Conclusions --- p.8-1 / Bibliography / Appendices
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Didaktika odložená daně / Didactics of Deferred TaxČechurová, Ludmila January 2010 (has links)
Diploma project is based on deferred tax and didactical theory and methods of teaching deferred tax. Project is interested in the essence of deferred income tax and in the principle of its recognition. Part of the project put mind to the timing differences and to the income tax rate. The assesment of the deferred tax liabilities or deferred tax assets took part of the project as well. Then the didactical principles are mentioned and the didactical analysis are accomplished. Also the analysis of the course books are done.
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Efeitos de densidades de Aeschynomene rudis Benth e seu controle com o herbicida Ethoxysulfuron em duas épocas de aplicação na cultura do arroz (Oryza sativa L.) irrigado. / Effects of Aeschynomene rudis Benth densities and its control with the herbicide ethoxysulfuron at two application timings in paddy rice (Oryza sativa L.).Marcio Luiz Adoryan 30 November 2004 (has links)
Com o objetivo de avaliar os efeitos de densidades de Aeschynomene rudis Benth. na cultura do arroz irrigado e a eficiência do herbicida ethoxysulfuron aplicado em duas épocas como pós-emergente, foi instalado um experimento no município de Taubaté, região do Vale do Paraíba-SP, no ano agrícola de 2001/2002. O cultivar de arroz Epagri 109 e a planta daninha A. rudis foram semeados em 30/10/2001 em solo drenado. Os tratamentos foram constituídos de quatro densidades de A. rudis (3, 6, 12 e 24 plantas por metro quadrado) e duas épocas de aplicação do herbicida ethoxysulfuron dentro de cada densidade (estádio de 4 e 6 folhas do A. rudis), e cinco parcelas testemunhas com densidades de 0, 3, 6, 12 e 24 plantas de A. rudis por metro quadrado sem a aplicação do produto, constituindo 13 tratamentos com 4 repetições, delineados em blocos ao acaso. O herbicida foi aplicado na dose de 80 g.ha-1, sendo adicionado à calda o adjuvante lauril éter sulfato de sódio na dose de 0,3 % base volume, e as pulverizações efetuadas nos dias 27/11/2001 e 04/12/2001. Os parâmetros avaliados foram: número de plantas, colmos e panículas por metro, altura das plantas de arroz, comprimento de panículas, número de espiguetas por panícula, número de grãos formados por panículas, rendimento de grãos, eficiência do herbicida no controle de A. rudis e fitointoxicação à cultura. Considerando-se os resultados obtidos pode-se concluir que: a) densidades de 3, 6, 12 e 24 plantas de A. rudis por metro quadrado, influenciam negativamente de forma linear, o número de colmos e de panículas por metro, o comprimento das panículas, o número de espiguetas e de grãos formados por panícula, o rendimento de grãos e o índice para colheita mecânica e não afetam o número de plantas por metro e a altura das plantas de arroz. b) o herbicida ethoxysulfuron é eficiente no controle de A. rudis nos estádios de 4 e de 6 folhas, nas densidades de 3, 6, 12 e 24 plantas por metro quadrado. c) ethoxysulfuron na dose de 80 g.ha-1, quando aplicado em pós-emergência precoce e mediana em densidades de 3, 6, 12 e 24 plantas de A. rudis por metro quadrado é seletivo para o cultivar de arroz Epagri 109, não interferindo nos parâmetros avaliados. / During the season 2001/2002, an experiment was conducted in Taubaté city, area of the Paraíba-SP valley, to evaluate the effect of Aeschynomene rudis Benth. densities on paddy rice, and the efficacy of the herbicide ethoxysulfuron applied in early and mid post emergence. The rice variety Epagri 109 and A. rudis were planted October 30, 2001 in dry soil. The treatments were four A. rudis densities (3, 6, 12 and 24 plants per square meter) and two application timings of the herbicide ethoxysulfuron in each density. The two application timings were at the 4 and 6 leaf stage of A. rudis. There were also untreated densities of 0, 3, 6, 12 and 24 plants of A. rudis per square meter without the herbicide application, resulting in 13 treatments with 4 replications delineated in randomized blocks. The herbicide was applied at 80 g.ha-1, with the adjuvant laurel ether sulfate of sodium at .3% v/v. The applications were made on November 27 and December 4, 2001. The assessed crop parameters were: number of plants, stems and panicles per meter, height of the plants, panicle length, number of spikelets by panicle, number of grains formed by panicles, income of grains, A. rudis control and crop damage. We can conclude from the results that A. rudis densities of 3, 6, 12 and 24 plants per square meter influence the crop negatively, in a linear way, the number of stems and panicles per meter, the length of the panicles, the number of spikelets and grains formed by panicles, the mechanical harvest index, and rice yield. There were no effects on the number of rice plants per meter or the height of the rice. Also, ethoxysulfuron was effective in controlling A. rudis at both the 4 and 6 leaf stage, in densities of 3, 6, 12 and 24 plants per square meter. Ethoxysulfuron at 80 g.ha-1, when applied early post or mid post emergence in densities of 3, 6, 12 and 24 plants per square meter was selective to the rice variety Epagri 109, not affecting the assessed parameters.
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Semáforos: gestão técnica, percepção do desempenho, duração dos tempos / Traffic signals: technical management, perception of performance, timingBarbara Stolte Bezerra 03 May 2007 (has links)
Neste trabalho são enfocados três aspectos relacionados com a operação de semáforos: gestão técnica, percepção do desempenho e duração dos tempos. No tocante à gestão técnica, é discutida sua importância em ser realizada de maneira adequada e é investigada a situação das cidades do país em relação à questão. A conclusão é que a situação da gestão semafórica nas cidades do país mostra-se bastante precária, com exceção de algumas grandes cidades. Com relação à percepção do desempenho das interseções semaforizadas, é pesquisada a percepção de motoristas do país quanto ao nível de serviço em semáforos isolados e em grupo de semáforos próximos dispostos ao longo de uma via, considerando os dois parâmetros determinantes da qualidade da operação: a demora e o número de paradas; e analisados os resultados obtidos à luz dos padrões estabelecidos no HCM-2000 e no HCM-1985. A conclusão é que os motoristas brasileiros se mostram mais tolerantes em relação a valores do HCM-2000. No que tange ao aspecto duração dos tempos, são investigadas as razões das programações de tempo empíricas utilizadas na prática, terem alguns resultados satisfatórios. São ainda apresentadas regras simples para a programação de tempos que permitam operar os semáforos com um desempenho aceitável quando não se dispõe de dados e/ou de conhecimento técnico adequado. / This work emphasizes three aspects related to traffic signals operation: technical management, perception of performance and signal timing. About technical management, it discusses the importance of a good management and evaluates the situation around the country. The conclusion is that management of traffic signals at brazilian cities is poor, with some exceptions at large cities. In relation to perception of performance, it researches country drivers perceptions related to level of service at single signalized intersections and group of signalized intersections, considering two parameters that determinate the quality of operation: delay and the number of stops; the results were analyzed and compared with the standard values of HCM-2000 and HCM-1985. It was found that brazilian drivers have more tolerance to the standard values of HCM-2000. About the signal timing, there were investigated the reasons of why empirical techniques used in practice at signalized intersections had some satisfactory results. In addition, it presents simple rules for timing traffic signals that will due an acceptable performance when the city does not have enough data, resources or specific technical knowledge.
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Influência de processos cognitivos em respostas posturais automáticas a perturbações extrínsecas / Influence of cognitive processes on automatic postural responses to extrinsic perturbationsCoelho, Daniel Boari 14 June 2017 (has links)
A capacidade de adaptação das respostas posturais automáticas de acordo com informações do contexto indica uma interação entre dois níveis de controle, em que o processamento cognitivo de alta ordem das características de uma perturbação iminente seria capaz de modular o controle postural em níveis inferiores do sistema sensoriomotor. Os estudos aqui propostos procuram responder quais informações sobre as características da perturbação são utilizadas pelo central set para modular as respostas posturais automáticas. A tarefa estudada consistiu na recuperação do equilíbrio da postura ereta em resposta à translação da base de suporte. No Experimento 1, foi avaliada a influência de dicas visuais sobre a amplitude de deslocamento da base de suporte em sequências repetitivas ou aleatórias de perturbação. No Experimento 2, a dica de amplitude de deslocamento foi dada por meio da sequência de perturbações, comparando-se tentativas repetidas em bloco, em sequência conhecida e em sequência aleatória. No Experimento 3, foi avaliado o efeito de incerteza tanto da amplitude da perturbação quanto do tempo de aplicação da perturbação. O Experimento 4 teve como propósito avaliar a interação entre dica temporal e tarefa cognitiva concomitante à recuperação do equilíbrio. Os resultados mostram que (a) informações prévias sobre a magnitude da perturbação postural parecem ser incapazes de modular respostas posturais automáticas; (b) modulação de respostas posturais automáticas a partir de uma sequência repetitiva de perturbações aparentemente está associada à adaptação do sistema sensoriomotor e não à participação de processamento cognitivo das características físicas da perturbação iminente; (c) previsibilidade temporal da perturbação postural induz uma otimização das respostas posturais automáticas; e (d) a execução de tarefa cognitiva no momento da perturbação inibe o ganho de estabilidade de respostas posturais automáticas conferido pela dica temporal. Como conclusão, parece haver uma limitação do processamento cognitivo em modular respostas posturais automáticas. Considerando-se que o conceito de central set expressa a noção de que processamento cognitivo de dicas contextuais é capaz de otimizar respostas posturais automáticas, nossos resultados sugerem a necessidade da revisão deste conceito amplamente empregado na literatura de controle postural / Adaptability of automatic postural responses according to context information indicates an interaction between two levels of control, in which the high-order cognitive processing of the perturbation characteristics would be able to modulate postural control in lower levels of the sensorimotor system. The studies proposed here intended to scrutinize what cues about the perturbation characteristics are used by the central set to modulate the automatic postural responses. The task studied consisted in the recovery of postural equilibrium in response to a posterior translation of the support base. In Experiment 1, it was evaluated the effect of precueing the displacement amplitude of the supporting base in repetitive or random perturbation sequences. In Experiment 2, precueing of the support base displacement was provided by the sequence of perturbations, comparing repetitive trials, known sequence and random sequence. In Experiment 3, we evaluated the effect of uncertainty about amplitude and time of perturbation. Experiment 4 aimed to evaluate the interaction of temporal precueing and a concurrent cognitive task on body equilibrium recovery. Results show that (a) previous information about perturbation magnitude seems to be unable to modulate automatic postural responses; (b) modulation of automatic postural responses from a repetitive sequence of perturbations is apparently associated with an adaptation of the sensorimotor system rather than to the participation of cognitive processing of the perturbation characteristics; (c) temporal predictability of the postural perturbation induces optimization of automatic postural responses; and (d) cognitive task execution at the time of the perturbation inhibits the gain of automatic postural responses stability provided by temporal precueing. As a conclusion, there seems to be a limitation of cognitive processing to modulate automatic postural responses. Considering that the concept of central set expresses the notion that cognitive processing of a contextual precue is able to optimize automatic postural responses, our results suggest the need for revision of this conceptualization widely used in the postural control literature
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Looking at the Marital Horizons of Emerging Adults Through the Lens of Identity FormationBelt, Dallin Alexander 01 March 2016 (has links)
Seventy years ago Erikson proposed successful identity formation in adolescence was the foundation for successful intimacy formation in young adulthood. With the extended period of identity exploration in emerging adulthood, it is unclear if intimacy formation continues to be connected to identity. The purpose of this study was to determine the relationship between identity in three domains of love, work, and worldview with long term views of intimacy using Marital Horizons Theory. Results from a sample of 777 college students in the Project READY dataset indicated that identity formation in love is positively associated with views of marriage, identity formation in work has no significant association with views of marriage, and identity formation in worldview is negatively associated with views of marriage. Implications for the transition into marriage and further identity research are discussed.
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