Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

Στην περιγραφόμενη διπλωματική εργασία μελετώνται τα αυτόνομα φωτοβολταϊκά συστήματα και γίνεται η μελέτη για την τροφοδότηση μιας αγροικίας στην περιοχή της Πάτρας. Τέτοια συστήματα αποτελούνται από φωτοβολταϊκά πλαίσια, συσσωρευτές και ηλεκτρονικές διατάξεις. Τα πλαίσια είναι αυτά που συλλέγουν την ηλιακή ακτινοβολία και μέσω ενός μηχανισμού, που λέγεται φωτοβολταϊκό φαινόμενο, την μετατρέπουν σε ηλεκτρική ενέργεια. Οι συσσωρευτές αποθηκεύουν ηλεκτρική ενέργεια, την οποία εκμεταλλευόμαστε όταν η ζήτηση είναι μεγαλύτερη από την παραγωγή. Οι ηλεκτρονικές διατάξεις, δηλαδή ο μετατροπέας τάσης και ο ελεγκτής φόρτισης, ευθύνονται για την μετατροπή της συνεχούς ισχύος σε εναλλασσόμενη καθώς, επίσης, και για την ομαλή λειτουργία του συστήματος. Αφού γίνει παρουσίαση όλης της θεωρίας και των μαθηματικών τύπων που απαιτούνται, γίνεται εφαρμογή τους μέσω του σχεδιασμού του κατάλληλου φωτοβολταϊκού συστήματος για την τροφοδότηση της αγροικίας. / The subject of this diploma thesis is the study of stand-alone photovoltaic systems. Such systems include photovoltaic modules, batteries, inverters and charge controllers as well. The photovoltaic modules collect solar energy and transform it into electrical energy via a mechanism that is called photovoltaic effect. Batteries storage electrical energy and are used when the electrical demand is greater than the energy generated by the modules. Inverters are used to convert DC power into AC power and charge controllers connect or disconnect the batteries from the system, as needed. After presenting the theory data required, a stand-alone photovoltaic system is designed so as to supply a country house.

Thesis (MScFor)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The practice of combining row and selective thinning in commercial pine plantation silviculture carries the risk of unwanted irregularities in tree distribution within the stand. This situation is aggravated with poor tree selection during marking. The potential consequences of poor tree selection are gaps created along row removals, which are necessary for access to harvesting operations. These gaps lead to spatially asymmetric growing space among adjacent trees. The effect of irregular stand structures on tree morphology and growth are investigated in this study, and are based on two stands of Pinus patula, (Schiede ex Schlechtendal et Cham.) in Langeni plantation, South Africa. This study focuses on two aspects. Firstly, a comparison between trees grown in all-sided and one-sided spatial competition situations in order to assess if there are differences in growth and selected quality parameters. Secondly, the mitigation of irregular structures using a simulation based study on changing the planting geometry in order to investigate the effect on harvesting in terms of stand impact, simulated harvesting productivity and harvesting system costs. Results showed that trees grown in an irregular competitive status have significantly larger crown diameters, crown lengths, longer and thicker branches, disproportionately one sided crown growth and a reduction in space-use efficiency. Simulations indicated that changing planting geometry from the current 2.7m x 2.7m to 2.3m x 3.1m and 2.4m x 3m would result in up to a 20% reduction of machine trail length and fewer rows being removed for machine access. The simulation of harvesting thinnings showed that various planting geometry alternatives increased harvesting productivity by 10% to 20% and reduced overall thinning harvesting cost by up to 11%. This study successfully investigated the factors that potentially negatively affect saw timber quality and volume production of the stand at final felling. It also illustrated the applicability of simulation methods for testing harvesting scenarios and developing economically viable alternatives. / AFRIKAANSE OPSOMMING: Die praktiese kombinasie van ryuitdunning en seleksiedunning in kommersiële denneplantasies dra die risiko van ongewensde onreelmatighede in die verspreiding van bome in die opstand. Hierdie situasie word vererger deur swak boomseleksie tydens die merk van dunnings. Die potensiële gevolge van swak boomseleksie is die ontstaan van onreelmatige gapings tussen boomkrone, veral langs die rydunnings, wat nodig is vir toegang tydens die ontginning van die hout. Dit lei daartoe dat die bome langs die dunningsrye asimmetriese ruimtes het om in te groei. Die effek van onreelmatige opstandstrukture op boom-morfologie en -groei word in hierdie studie ondersoek in twee Pinus patula, (Schiede ex Schlechtendal et Cham.) vakke te Langeni plantasie, Suid-afrika. In die studie word daar gefokus op twee aspekte. Eerstens word bome wat onder toestande van eweredige ruimetlike kompetisie groei vergelyk met die wat onder toestande van eensydige ruimtelike kompetisie groei om sodoende vas te stel of daar verskille is in die groeipatroon aan die hand van geselekteerde gehalteparameters. Tweedens word daar gefokus op die verbetering van onreelmatige opstandstrukture deur gebruik te maak van ’n simulasie-gebasseerde studie om veranderinge in die aanplantingsgeometrie te ondersoek met die doel om die effek van plantspasieering op ontginningsimpakte, gesimuleerde ontginningsproduktiwiteit en -sisteem koste te bepaal. Die resultate het getoon dat bome wat onder toestande van onreelmatige spasieering en kompetisie groei krone met groter deursnee asook langer lengtes ontwikkel, langer en dikker takke het, disproporsionele, eensydige kroongroei en ’n reduksie in ruimte-gebruik toon, wat die groeidoeltreffendheid nadelig beinvloed. Simulasies met betrekking tot die verandering in boomaanplantgeometrie vanaf die huidige 2.7m x 2.7m na 2.3m x 3.1m en 2.4m x 3m het gedui op ’n reduksie van 20% in die masjienpadafstand en na minder rye wat uitgehaal moes word om die toegang van masjiene moontlik te maak. Die simulasie van die ontginning van dunnings het getoon dat verskillende aanplantgeometriealternatiewe die ontginningsproduktiwiteit met 10% tot 20% verbeter het, en die algehele dunningsoeskoste met tot 11% verminder het. In hierdie studie is die faktore, wat die gehalte van saaghoutkwaliteit en volume tydens die finale oes van die plantasie potensieel negatief mag beinvloed, suksesvol ondersoek. Dit illustreer ook die geskiktheid van simulasietoepassings vir die toets van ontginningsalternatiewe en die ontwikkelling van meer ekonomies voordelige praktyke .

Introdução: A força muscular periférica e respiratória pode estar reduzida em pacientes com doença pulmonar obstrutiva crônica (DPOC). O impacto desta redução sobre a capacidade de realizar atividades e exercícios não é bem conhecida. Objetivos: Comparar a força muscular periférica e respiratória e o desempenho no teste da caminhada de 6 minutos (TC6) e no teste de senta e levanta de 1 minuto (TSL) em indivíduos com e sem DPOC e estudar o impacto da força muscular nos dois testes. Métodos: Foram estudados 21 pacientes com DPOC (13 homens, idade de 63±7 anos, volume expiratório forçado no primeiro segundo - VEF1 – 1,14±0,54, 42±18% do previsto) e 21 indivíduos sem DPOC (13 homens, idade 64±7 anos, VEF1 2,64±0,65, 106±21% do previsto). Todos os indivíduos realizaram espirometria, avaliação da pressão inspiratória máxima (PImáx) e expiratória máxima (PEmáx), teste de uma repetição máxima (1RM) para avaliar força do quadríceps, TC6 e TSL. Resultados: Quando comparados com controles pacientes com DPOC apresentaram valores inferiores de PImáx (77±23 cm H2O vs 102±18 cm H2O, p=0,0001), PEmáx (100±26 cm H2O vs 127±23 cm H2O, p=0,001), força do quadríceps (17±5 Kg vs 23±4 Kg, p=0,0001), distância no TC6 (405±76 m vs 539±48 m, p=0,0001) e repetições no TSL (25±6 vs 35±6, p=0,0001). No grupo de 42 indivíduos a distância percorrida no TC6 se associou com o VEF1 (r=0,80, p=0,0001), com a PImáx (r=0,59, p=0,0001), com a PEmáx (r=0,63, p=0,0001), com a SpO2 basal (r=0,61, p=0,0001) e com a força do quadríceps (r=0,63, p=0,0001). Num modelo multivariado o VEF1, a PImáx e a dispneia basal explicaram 81% da variabilidade da distância percorrida no TC6. Em relação ao TSL as melhores correlações foram observadas com o VEF1 (r=0,55, p=0,0001) e com a força do quadríceps (r=0,50, p=0,0001) e associação mais fraca foi observada com as pressões respiratórias máximas (r=0,34, p=0,02). A distância percorrida no TC6 se associou com o número de repetições no TSL (r=0,61, p=0,0001). Conclusões: Pacientes com DPOC tem redução da força muscular do quadríceps e das pressões respiratórias e um pior desempenho no TC6 e no TSL em relação aos controles. Tanto a força muscular do quadríceps como as pressões respiratórias influenciam o desempenho nos dois testes. Entretanto, o impacto da força do quadríceps sobre a distância percorrida parece depender do VEF1. Observamos uma relação forte entre a distância percorrida e o número de elevações no TST, sugerindo que o TST possa ter um papel na avaliação funcional de pacientes com DPOC. / Introduction: Peripheral and respiratory muscle strength may be reduced in patients with chronic obstructive pulmonary disease (COPD). The impact of this reduction on the ability to perform activities and exercises is not well known. Aims: To compare the peripheral and respiratory muscle strength and the performance in a 6-minute walk test (6MWT) and a sit-to-stand test (STST) in subjects with and without COPD and to study the impact of the muscle strength on both tests. Methods: We studied 21 patients with COPD (13 men, age 63±7 years, forced expiratory volume in one second, FEV1 1.14±0.54, 42 ± 18% predicted ) and 21 subjects without COPD (13 men, age 64±7 years, FEV1 2.64±0.65, 106±21% predicted). All subjects underwent spirometry, maximal inspiratory (MIP) and expiratory pressure (MEP), one-repetition maximum (1RM) to evaluate quadriceps strength, 6MWT and STST. Results: When compared to controls patients with COPD showed lower values of MIP (77±23 cm H2O vs. 102±18 cm H2O, p=0.0001), MEP (100±26 cm H2O vs 127±23 cm H2O, p=0.001), quadriceps strength (17 ± 5 kg vs. 23 ± 4 kg, p=0.0001), distance in 6MWT (405±76 m vs 539±48 m, p = 0.0001) and repetitions in STST (25±6 vs 35±6, p=0.0001). The walked distance was associated with FEV1 (r=0.80, p=0.0001), MIP (r=0.59, p=0.0001), MEP (r=0.63, p=0.0001), baseline SpO2 (r=0.61, p=0.0001) and quadriceps strength (r=0.63, p=0.0001). In a multivariate model FEV1, MIP and baseline dyspnea explained 81% of the walked distance variance in 6MWT. Regarding the TSL, the best correlations were observed with FEV1 (r=0.55, p=0.0001) and quadriceps strength (r=0.495, p = 0.0001) while a weaker association was observed with the maximal respiratory pressures (r=0.34, p=0.02). The distance walked in 6MWT was associated with the number of repetitions in TSL (r=0.61, p=0.0001). Conclusions: Patients with COPD have reduced quadriceps muscle strength and respiratory pressures and a worse performance in the 6MWT and STST in relation to controls. Both the quadriceps muscle strength and respiratory pressure influenced the performance in both tests. However, the impact of quadriceps strength on the walked distance seems to depend on FEV1. We observed a strong relationship between distance and number of elevations in STST, suggesting that STST may have a role in the functional evaluation of patients with COPD.

The aim of the thesis was to evaluate the damage caused by bark beetle on forest stand in the district of Stribne Hute which is managed by Forest Management Tabor. Forest stands are being damaged by various harmful effects which reduce theirs ecological stability. The damage is defined as a reduction of utility value or as a damage caused by adverse effects. Spruce bark beetle (Ips typographus L.) is significant part of entomocenosis and it is being considered as the most serious pest of spruce stands. Data from 2007 - 2012 were processed, it consisted of bark beetle matter production records, evaluation of timber harvest (especially random harvest) and calculation of revenues. The price lists of average values of spruce logs KH and A/B quality was used to calculate revenues from bark beetle matter and standard quality. The comparison of revenues was used to determinate the loss caused by bark beetle. Losses were minimal due to the quantity of bark beetle which did not reach state of emergency.

This thesis summarizes the results obtained from a study of long-term field trials with permanent grassland, which based on Faculty of Agriculture, University of South Bohemia in the České Budějovice between years 2010 - 2013. Permanent grasslands are managed in different ways (mowing, mulching, fallow) and the intensity of exploitation (harvested 1 - 3 times a year, fertilization). The work was focused on the evaluation of changes in growth composition, biomass production and dry matter content of hay variants. Also were evaluated biodiversityand grazing value of the crop stand. Before each harvest (mowing or mulching) was evaluated growth composition of experimental grasslands on an area of 20 m2. Plant species coverage of individual agro botanical groups was estimated by the reduced projective dominance (% D). Harvested biomass of grassland was considered and sample mown every variantof the experiment was dried (dry matter content). Species diversity was expressed as the number of species and species diversity was expressed in the form of Simpson's index. It was also calculated value describing the quality and productivity ofthe crop stand.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Understanding the initial development in consortiated systems are vital to decide about practices to obtain a sustainable productivity, in relation to environmental resources in an agrossilvicultural site. Due to this, this study had as objective: - to evaluate the agricultural productivity in agroforestry systems with different arrangements of the forest species; - to determine the biomass and nutrients accumulation in different species involved in the system; - to evaluate initial growth of monospecifical and mixed stands of Eucalyptus urograndis and Acacia mearnsii; - to determine soil occupation by root system of Eucalyptus urograndis and Acacia mearnsii in monoespecifical and mixed stands and also Acacia mearnsii nodules in these systems. For that, an experimental field was installed in Bagé-RS, which is composed by five treatments with simple combination and arrangements of Eucalyptus urograndis (E) and Acacia mearnsii (A) (100E; 100A; 50E:50A; 75E:25A e 25E:75A), in a randomized blocks design, with three repetitions, with corn cultivaded in the six first months. Growth evaluations for the aerial part in agroforestry system were done at 6 and 18 months age, and root system evaluation was done at of 8 and 18 months age. Initial growth in diameter, total height and wood production of Eucalyptus urograndis and Acacia mearnsii didn t differ significantly (p < 0.05) in different treatments. Forest species consortion provided a positive interspecific effect in Eucalytpus urograndis leaf area index. Total above ground biomass was statistically equal (p < 0.05) between monocultive and mixed stands of forest species, but when it was evaluated in compartments, a competitive interspecific interaction was observed of eucalyptus upon black-wattle, causing a reduction on crown biomass formation. Total production of maize (Zea mays), consortiated with monoespecifical and mixed stands of forest species, did not differ statistically (p > 0.05) among the tested treatments. Due to the great nutrients export through maize harvest, it is necessary, even with straw maintenance in agroforestry systems, to make a nutritional reposition, mainly with P and N in the following cultives, because of the great amount that are exported through grains, which comes to 68,1 and 51,7%, respectively, in relation with the total accumulated on biomass. Root system, independent of cropping system, reaches a maximum projection in the vicinity of 120 cm from the stem of the tree at 8 months old, although at 18 months it reaches the whole utile are in each tree. Fine roots density at 8 months, both for root system length and biomass for Eucalyptus urograndis and Acacia mearnsii in monoculture and in mixed stands, show the same behavior for soil layers occupation. Interespecif interactions and intraespecific interactions were not observed between root systems of eucalyptus and blackwattle, until 18 months. Nodules biomass showed a very variable distribution and didn t show differences between monocultive and mixed stand of Acacia mearnsii. Higher density of roots and nodules is located in the layer from 5 10 cm depth, close to tree stem followed by diagonal and planting inter-row. Nutrients competition can be considered as minimum, between mayze and forest species, due to its small root system projection during crop cultivation (6 initial months). / O entendimento do desenvolvimento inicial de sistemas consorciados é vital para a tomada de decisões acerca de possíveis práticas para obtermos uma produção sustentável, em relação aos recursos ambientais, em um determinado sítio agrossilvicultural. Devido a isso, o presente estudo teve como objetivos avaliar a produtividade agrícola de sistemas agrossilviculturais com diferentes arranjos de espécies florestais; determinar o acúmulo de biomassa e nutrientes nas diferentes espécies envolvidas no sistema; avaliar o crescimento inicial de povoamentos monoespecíficos e mistos de Eucalyptus urograndis e Acacia mearnsii; determinar a ocupação do solo pelo sistema radicular do Eucalyptus urograndis e Acacia mearnsii em povoamentos monoespecíficos e mistos e a nodulação da Acacia mearnsii nestes sistemas. Para isso, instalou-se uma área experimental no município de Bagé-RS, a qual está constituída por cinco tratamentos com combinações e arranjos simples de Eucalyptus urograndis (E) e Acacia mearnsii (A) (100E; 100A; 50E:50A; 75E:25A e 25E:75A), num delineamento de blocos ao acaso com três repetições, com cultivo de milho nos seis primeiros meses. As avaliações de crescimento da parte aérea do sistema agrossilvicultural foram realizadas aos 6 e 18 meses de idade dos povoamentos. Já a avaliação do sistema radicular foi realizada aos 8 e 18 meses. O crescimento inicial em diâmetro, a altura total e a produção de madeira de Eucalyptus urograndis e da Acacia mearnsii não diferiram significativamente (p < 0,05) nos diferentes tratamentos. O consórcio das espécies florestais provocou um efeito positivo interespecífico no índice de área foliar do Eucalytus urograndis. A biomassa total acima do solo foi igual estatisticamente (p < 0,05) no monocultivo e no plantio misto das espécies florestais, mas quando avaliado por compartimentos, verificou-se interação competitiva interespecífica do eucalipto sobre a acácia-negra, ocasionando a redução da formação de biomassa de copa. A produção total de biomassa do milho (Zea mays), consorciado com plantios monoespecíficos e mistos das espécies florestais, não diferiu estatisticamente (p > 0,05) entre os tratamentos testados. Devido à grande exportação de nutrientes pela colheita do milho, deve-se, mesmo com a manutenção da palhada nos sistemas agrossilviculturais, fazer reposição nutricional principalmente de P e N em cultivos seguintes, em decorrência da grande quantidade que é exportada pelos grãos, que chega a 68,1 e 51,7%, respectivamente, em relação ao total acumulado na biomassa. O sistema radicular, independentemente do sistema de cultivo, atinge uma projeção máxima no entorno de 120 cm de distância do tronco da árvore aos 8 meses de idade; já aos 18 meses atinge toda a área útil de cada árvore. A densidade de raízes finas aos 8 meses de idade, tanto para o comprimento como para a biomassa do sistema radicular do Eucalyptus urograndis e Acacia mearnsii em monocultivo e em plantio misto, possui o mesmo comportamento para a ocupação das diferentes camadas do solo. Não foram observadas interações interespecíficas ou intraespecíficas entre os sistemas radiculares do eucalipto e da acácia-negra até os 18 meses de idade. A biomassa de nódulos teve distribuição muito variável e, conseqüentemente, não apresentou diferenças entre o monocultivo e o cultivo misto de Acacia mearnsii. A maior densidade de raízes e nódulos encontra-se na camada de 5 a 10 cm de profundidade, nas proximidades do tronco da árvore e na linha de plantio seguido pela diagonal e entrelinha de plantio. A competição por nutrientes pode ser considerada mínima, entre o milho e as espécies florestais, devido à pequena projeção do sistema radicular das árvores durante o cultivo agrícola (6 meses iniciais).

Made available in DSpace on 2016-12-06T17:07:19Z (GMT). No. of bitstreams: 1 Andre Rocha.pdf: 2659050 bytes, checksum: ab889033d038c34c38a4e174f6d78945 (MD5) Previous issue date: 2009-04-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Hemiparesis following stroke reduces the ability to use the involved lower extremity during the sit-to-stand (STS) transfer, thus affecting the performance. This study investigated in hemiparetic subjects the combined effects of the non-affected lower limb (NA) constraints by supporting it on a step and the seat height for the weight-bearing on the affected lower limb (AF) and the reduction of asymmetry during STS. Thirteen adult subjects (60,4 ± 5,7 years) were selected, of both sexes, with hemiparesis due to stroke in chronic stage (43,7 ± 50 months). They had mild to moderate impairments on the Fugl-Meyer Scale (24,7 ± 4,9 points). The participants underwent clinical evaluations and biomechanical analyses of the kinetics and kinematics of the movements of interest. Individuals stood up from a instrumented bench at two seat heights, 100% (normal) and 130% (elevated) from the knee height (KH). There were four conditions of the feet: (1) spontaneous (SPO), (2) symmetric (SYM), (3) asymmetrical (ASS) with the NA limb in front of the AF, and (4) step (STP) of the NA limb supported on a step. Force plates and a kinematic system were used for analyses of the vertical component (Fz) of the ground reaction forces and the kinematic behaviors of the resulting movement. The results showed significant decreases of the asymmetry in the step condition compared to the positions of the SPO (p<0001), SYM (p<0001) and ASS (p=0023). The angles of hip, knee and ankle reached normal values. With the elevation of the seat height at 130%, KH had significant reductions in the time of movement and the anterior displacement of the trunk (p<0001 both). The restriction of the AF by the step was efficient in reducing the asymmetry in the STS and may be a therapeutic resource to be used in reversing the learned non-use. Raising the seat height reduced the time and displacement of the trunk, there facilitated reaching the upright position even with the use of step. The use of constraint as a strategy for training is suggested to reduce the asymmetry in the STS. / A hemiparesia após um Acidente Vascular Encefálico (AVE) compromete a capacidade de usar a extremidade inferior acometida durante transição de sentado para de pé (ST-DP), afetando o desempenho funcional. Este estudo investigou, em indivíduos hemiparéticos, o efeito combinado da restrição do membro inferior não-afetado (MINA) apoiado em um step e da altura do assento, sobre a transferência de peso para o membro inferior afetado (MIAF) e redução da assimetria durante o movimento ST-DP. Foram selecionados 13 indivíduos adultos (60,4 ± 5,7 anos), de ambos os sexos, com seqüela de hemiparesia devido a AVE na fase crônica (43,7 ± 50 meses) e comprometimento de leve a moderado na Escala de Fugl-Meyer (24,7 ± 4,9 pontos). Os participantes realizaram avaliações clínicas e biomecânicas através de análise cinética e cinemática do movimento de interesse. Os indivíduos levantaram de um banco instrumentado a partir de duas alturas de assento, 100% (normal) e 130% (elevada) da altura do joelho (AJ), e em 4 condições dos pés: (1) espontânea (ESP); (2) simétrica, SIM; (3) assimétrica (ASS) - membro não-afetado à frente; e (4) step (STP) - membro não-afetado apoiado em um step. Plataformas de força e sistema de cinemetria foram empregados respectivamente para análise da componente vertical (Fz) da força de reação do solo e do comportamento cinemático resultantes do movimento. Os resultados mostraram uma diminuição significativa da assimetria na condição step em relação as posições ESP (p < 0,001), SIM (p <0,001) e ASS (p =0,023), influenciando positivamente os ângulos de quadril, joelho e tornozelo para valores mais próximos dos normais. Com a elevação da altura do assento à 130%AJ foi observada uma redução significativa do tempo de movimento e deslocamento anterior do tronco (p < 0,001para ambos). A restrição do MINAF pelo step mostrou-se eficiente na diminuição da assimetria durante o ST-DP e pode ser um recurso terapêutico utilizado na reversão do desuso aprendido. Elevar a altura do assento diminuiu as demandas de tempo e deslocamentos do tronco, facilitando a aquisição da postura em pé mesmo com o emprego do step. Sugere-se o uso da restrição como uma estratégia de treinamento visando reduzir a assimetria durante o ST-DP.

Made available in DSpace on 2016-12-06T17:42:05Z (GMT). No. of bitstreams: 1 PGPV14DA011.pdf: 1428690 bytes, checksum: 449aef7542bd13e0b624b66ceb10523f (MD5) Previous issue date: 2014-10-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The proper choice of plant arrangement is important to maximize maize grain yield. This work was carried out aiming to evaluate the best strategies to manipulate plant arrangement in order to reach grain yields higher than 18,000 kg ha-1. Four field experiments were set during the 2010/2011 and 2011/2012 growing seasons. In the first experiment, the effect of increasing plant density was assessed. The plant populations of 3, 5, 7, 9 and 11 pl m-2 were tested at two row spacing (40 and 80 cm). In the second trial, the effect of reducing row spacing was studied. Five row spacings were tested: 40, 60, 80, 100 cm and twin rows. Each row spacing was tested at two plant densities (7 and 9 pl m-2). In the third trial, plant uneven emergence at the sowing row was evaluated. Five levels of unevenness in plant emergence were studied: 0, 2.5, 5, 7.5 and 10 days. In the level 0, all seeds were sowed in the same day. In the other treatments, half seeds were sowed in day 0 and the other half 2,5, 5, 7.5 and 10 days after. It the forth trial spatial uneven plant distribution in the sowing row was simulated. Five levels of spatial unevenness were addressed: 0, 25, 50, 75 and 100 of the variation coefficient (C.V.). In the level 0, all seeds were placed at the same distance from each other in the sowing row. Uneven temporal and spatial distribution was studied at 18 19 two row spacings: 40 and 80 cm. In the first experiment, grain increased linearly with the increment in plant population from 3 to 11 pl m-2 when maize was grown with the row spacing of 40 cm. In the second trial, grain yield was greater with 9 pl m-2 than with 7 pl m-2 and row spacing did not affect the crop productivity. In the third experiment, the increase in temporal variability of plant emergence decreased grain yield when maize was grown with rows 80 cm apart. In the fourth trial, grain yield was reduced by the increment in spatial variability among plants at the sowing row when the crop was grown with the row spacing of 40 cm. The use of supra-optimum plant densities ( 9 to 11 pl m-2), associated to narrow row spacing (40 cm), are efficient strategies to manipulate plant arrangement in order to lift maize grain yield above 18,000 kg ha-1, as long as the plants are evenly distributed in space and time at the sowing rows / A escolha adequada do arranjo de plantas é importante para potencializar o rendimento de grãos do milho. Este trabalho foi conduzido com o intuito de identificar as melhores estratégias de manipulação do arranjo de plantas para alcançar tetos produtivos superiores a 18.000 kg ha-1. Foram conduzidos quatro experimentos nas safras 2010/2011 e 2011/2012. No primeiro avaliou-se o efeito do incremento na densidade de plantas sobre o desempenho agronômico do milho. Foram testadas as densidades de 3, 5, 7, 9 e 11 pl m-2, nos espaçamentos entre-linhas de 40 e 80 cm. No segundo avaliou-se o impacto da redução do espaçamento entre-linhas no potencial produtivo do milho. Foram avaliados os espaçamentos entre-linhas de 100, 80, 60 e 40 cm e o de linhas gêmeas, nas densidades de 70.000 e 90.000 pl ha-1. No terceiro quantificou-se o efeito da irregularidade temporal na emergência das plantas na linha de semeadura sobre o rendimento de grãos. Foram testados cinco níveis de desuniformidade temporal, equivalentes a 0, 2,5, 5,0, 7,5 e 10 dias. No nível 0 todas as sementes foram semeadas no mesmo dia. Nos demais níveis, metade das sementes foi semeada no dia 0 e a outra metade 2,5, 5,0, 7,5 e 10 dias após. No quarto experimento analisou-se o efeito da desuniformidade espacial na linha sobre o rendimento de grãos do milho. Foram testados cinco níveis de desuniformidade espacial, equivalentes a 0, 25, 50, 75 e 100 % do coeficiente de variação, onde o nível 0 equivale as plantas uniformemente distribuídas nos sulcos. Cada nível de desuniformidade temporal e espacial foi avaliado nos espaçamentos entre-linhas de 40 e 80 cm. No primeiro ensaio, o rendimento de grãos aumentou linearmente com o incremento na densidade de plantas no espaçamento de 0,4m entre-linhas. No segundo ensaio, os rendimentos foram maiores na densidade de 9 pl m-2 do que na de 7 pl m-2 e não houve diferenças significativas no rendimento de grãos entre os cinco espaçamentos entre-linhas. No terceiro trabalho, o aumento da variabilidade temporal das plantas na linha diminuiu o rendimento de grãos do milho quando o mesmo foi cultivado com espaçamentos entre-linhas de 80 cm. No quarto ensaio, o rendimento de grãos reduziu com o aumento do C.V na distribuição espacial de plantas quando o milho foi cultivado no espaçamento entre-linhas de 40 cm. A utilização de densidades supra-ótimas (9 a 11 pl m-2) e de espaçamento entre-linhas reduzido (40-50 cm) são estratégias efetivas de manipulação do arranjo de plantas para alcançar produtividades superiores a 18.000 kg ha-1 em lavouras com distribuição espacial e temporal uniforme das plantas na linha de semeadura

Made available in DSpace on 2016-12-12T17:32:56Z (GMT). No. of bitstreams: 1 Resumo Daiane Medeiros.pdf: 112848 bytes, checksum: 243c03f59b51fcd3929df4053f3f22ac (MD5) Previous issue date: 2014-06-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this research was to analyze the influence of different bench heights and foot placement in the dynamic postural control in children with Cerebral Palsy during the sit-to-stand (STS) task from a kinetic and kinematic perspective. The sample consisted of fourteen children with Cerebral Palsy (CP) (mean age, 8,43±3,00) and fourteen typically developing to control group (CG) (mean age, 8,43±3,00). The children with CP were divided in two groups: children able to perform independently the STS (CPI) and children who need support to perform the STS (CPS). The balance was assessed by the Pediatric Balance Scale (PBS). The motor function of children with CP was classified using the Gross Motor Function Classification System (GMFCS). Kinematic and kinetic data were recorded and analyzed during the sit-to-stand task with different bench height and foot placement. The kinetic variables analyzed were Area of center of pressure (COP), COP anterior-posterior direction (COPAP), COP medial-lateral direction (COPML) and Total average speed of COP (TASCOP). And the kinematic variables were linear displacement of the shoulder (x and y), linear displacement of the knee (x and y), average speed of STS and time duration of STS. Regarding the PBS it was observed that CPS showed significant reduction in balance when compared to other groups and less displacement of center of pressure (COP). The CPI exhibited significant increase in displacement of COPML when compared to the CG. The results showed that children with PC require more time to complete the STS task than CG. The CPS presented lower linear displacement of the shoulder and knee than the other groups. During the high bench condition the linear displacement of the shoulder and knee were reduced too. We concluded that the different conditions did not influence postural control when assessed by kinetic variables. The CPI showed higher displacement of COPML when compared to CG. This indicates the use of different motor strategies for the STS task. The different bench heights influenced the kinematic variables, so that the high bench reduced the linear displacement of the shoulder and knee. / Este estudo tem como objetivo analisar a influência de diferentes alturas de banco e posicionamento dos pés no controle postural de crianças com PC durante a transferência de sentado para em pé (TSP), sob uma perspectiva cinética e cinemática. A amostra foi composta por 14 crianças com Paralisia Cerebral (PC) (média de idade, 8,43±3) e 14 crianças típicas (média de idade 8,43±3) para o Grupo Controle (GC). As crianças com PC foram divididas em dois grupos: Grupo PC sem apoio (GPCSA) e Grupo PC com apoio (GPCCA). O equilíbrio das crianças do presente estudo foi avaliado por meio da Escala de Equilíbrio Pediátrica (EEP). A função motora de crianças com PC foi classificada de acordo com o Sistema de Classificação da Função Motora Grossa (GMFCS) e avaliação cinética e cinemática da TSP foram realizadas em diferentes alturas de banco e posicionamento dos pés. Em relação à EEP o GPCCA apresentou redução significativa do equilíbrio quando comparado aos demais grupos, o mesmo apresentou menores valores do deslocamento do COP. O GPCSA exibiu aumento significativo do deslocamento do COPML quando comparado ao GC. As crianças com PC apresentaram maior duração de tempo para realizar a tarefa. O GPCCA apresentou menor deslocamento linear do ombro e joelho e a condição de banco alto também reduziu estes deslocamentos. Pode-se concluir que as diferentes condições não influenciaram o controle postural avaliado por meio das variáveis cinéticas. O GPCSA apresentou maior deslocamento do COPML quando comparado às crianças típicas, o que indica que essas utilizam diferentes estratégias motoras durante a TSP. As diferentes alturas de banco influenciaram as variáveis cinemáticas, de modo que as condições com o banco alto reduziu o deslocamento do ombro e do joelho