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Search Results: 1 - 10 of 47259 matches for " Rui Manuel Almeida Machado "
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Produ??o de cebola de dias curtos no Alentejo. Influência da aduba??o localizada
Machado,Rui Manuel Almeida; Oliveira,Maria do Rosário Gamito;
Revista de Ciências Agrárias , 2008,
Abstract: in alentejo region low temperatures and soil waterlogging during autumn- winter season are limiting factors for vegetable production under field conditions. short -day onions can be an option to surpass these restrictions. the aim of the present work was to evaluate the effect of short - day onion cultivars and band placement of the fertilizer on onion production in alentejo, planted during the autumn. the experiment was carried out at mitra research station of the university of évora and the treatments were: short - day onion cultivars (?spring star? and ?mineutaka?) and fertilizer application method at plantation (broadcasting and banding at 10 cm ± 2 depth, under the crop row). fertilizer banding did not affect root density (cm cm-3) under the crop row, nor onion bulb yield which was 8.3 and 9.0 kg m-2 for ?spring star? and ?mineutaka? respectively. since the studied cultivars presented resistance to waterlogging and low temperature that occurred during the growing season with good production, short - day onion has great agronomical potential for alentejo region. additionally, having in consideration the growing season conditions, water will not be a limiting factor.
Produ o de cebola de dias curtos no Alentejo. Influência da aduba o localizada Short-day onion bulb yield in Alentejo. Influence of fertilizer band placement
Rui Manuel Almeida Machado,Maria do Rosário Gamito Oliveira
Revista de Ciências Agrárias , 2008,
Abstract: As baixas temperaturas e o fácil encharcamento da maioria dos solos do Alentejo constituem uma restri o à produ o de hortícolas ao ar livre, no Outono-Inverno. A cebola de dias curtos pode constituir uma op o pela sua capacidade para superar estes constrangimentos. Assim, este trabalho teve como objectivo estudar o comportamento de duas cultivares de cebola de dias curtos, plantadas no Outono e a influência da localiza o da aduba o aquando da planta o. O ensaio decorreu na herdade experimental da Mitra da Universidade de évora e os tratamentos em estudo foram: a cultivar de cebola de dias curtos (“Spring Star” e “Mineutaka”) e o método de aplica o do adubo à planta o (distribui o a lan o e localiza o do adubo numa faixa a 10 cm ± 2 de profundidade, sob a linha de cultura). A aduba o localizada n o afectou a densidade radical (cm cm-3) sob a linha de cultura, nem a produ o comercial de bolbos a qual foi respectivamente para a “Spring Star” e “Mineutaka” de 8,3 e 9,0 kg m-2. Visto as cultivares estudadas terem apresentado resistência ao excesso de água e às baixas temperaturas que ocorreram durante o ciclo, com produ es consideráveis, a cebola de dias curtos apresenta-se como uma cultura com elevado potencial agronómico para o Alentejo. Adicionalmente, dada a época em que é realizada a cultura a água para a rega n o será um factor limitante. In Alentejo region low temperatures and soil waterlogging during Autumn- Winter season are limiting factors for vegetable production under field conditions. Short -day onions can be an option to surpass these restrictions. The aim of the present work was to evaluate the effect of short - day onion cultivars and band placement of the fertilizer on onion production in Alentejo, planted during the autumn. The experiment was carried out at Mitra Research Station of the University of évora and the treatments were: short - day onion cultivars (“Spring Star” and “Mineutaka”) and fertilizer application method at plantation (broadcasting and banding at 10 cm ± 2 depth, under the crop row). Fertilizer banding did not affect root density (cm cm-3) under the crop row, nor onion bulb yield which was 8.3 and 9.0 kg m-2 for “Spring Star” and “Mineutaka” respectively. Since the studied cultivars presented resistance to waterlogging and low temperature that occurred during the growing season with good production, short - day onion has great agronomical potential for Alentejo region. Additionally, having in consideration the growing season conditions, water will not be a limiting factor.
Efeito da fertiliza??o azotada na dinamica de enraizamento e na produ??o comercial de cebola de dias médios no alentejo
Machado,Rui Manuel Almeida; Shahidian,Shakib; Pivetta,Carina Rejane; Oliveira,Maria do Rosário Gamito;
Revista de Ciências Agrárias , 2009,
Abstract: intermediate-day onions (cv. gilmar) rooting patterns, soil availability no3-, leaf n concentration and commercial yield were evaluated in a field trial where four nitrogen fertilizer rates (0, 37, 74 and 111 kg n ha-1) were applied into four split applications, following a randomized block design with four replications. root length, soil availability no3-, and leaf n concentration were evaluated at four dates during growing season (33, 57, 96 and 127 days after planting). root length density (cm cm-3) at different sampling dates, locations (under the bulb and at 4 cm from the plant row) and depths was not affected by nitrogen level. for all sampling dates about 65 to 100 % of the root length was concentrated in the top 10 cm of the soil profile, under the bulb and the maximum root length density was 1.88 cm cm-3. the maximum rooting depth ranged from 20 and 30 cm, not exceeding 10 cm in depth, up to 32 days after planting. under the conditions of the experiment, results recommend an application of 30 kg ha-1 of nitrogen at planting and an increasing of the amount of nitrogen applied (16.2% of total n applied) at bulb initiation. marketable onion yield increased with the level of nitrogen but the production obtained with the application of 74 kg ha-1 (5.12 kg m-2) and 111 kg n ha-1 (6.59 kg m-2) did not differ significantly.
Influência do azoto no crescimento da cebola antes do inicio da forma??o do bolbo
Machado,Rui Manuel de Almeida; Alpendre,Pedro Fraz?o; Shahidian,Shakib; Jesus,Ricardo Azevedo;
Revista de Ciências Agrárias , 2012,
Abstract: the effect of nitrogen application prior transplanting on aboveground growth and root growth of the short- day onions (cv. mineutaka), from transplanting to bulb initiation was studied in a pot experiment. the pot experiment was carried out with ten treatments, including two soil types (clay-sandy and sandy soil) and five levels of n application (0, 10, 30, 40 and 50 kg n ha-1) applied prior transplanting. aboveground and root growth and biomass allocation (root: shoot ratio) were not significantly affected by nitrogen level or interaction nitrogen level * soil type. the residual soil inorganic n and the released n from organic matter, most nitrogen introduced by irrigation water (20 mg n plant-1), was sufficient for plant growth before bulb initiation. plant growth and biomass allocation were significantly affected by soil type. plant biomass in clay-sandy soil was 30% higher than in sandy soil. total root length of plants grown in sandy soil (43.74 m) was 2.3 times higher than in clay-sandy soil (19.26 m). root biomass, specific root length (slr) and root-shoot ratio were higher in plants grown in sandy soil.
Efeito da fertiliza o azotada na dinamica de enraizamento e na produ o comercial de cebola de dias médios no alentejo Nitrogen fertilization effects on rooting pattern and yield of intermediate-day onions bulb in alentejo region
Rui Manuel Almeida Machado,Shakib Shahidian,Carina Rejane Pivetta,Maria do Rosário Gamito Oliveira
Revista de Ciências Agrárias , 2009,
Abstract: Este trabalho teve como objectivo estudar a influência da aplica o de diferentes quantidades de azoto, repartidas por quatro aplica es, na disponibilidade de azoto nítrico no solo, no comprimento radical, na concentra o de azoto nas folhas e na produ o comercial de cebola de dias médios (cv. Gilmar) no Alentejo. O ensaio decorreu na Centro de estudos e experimenta o da Mitra da Universidade de évora e foi delineado em blocos casualizados com quatro repeti es. Os tratamentos consistiram em 4 níveis de aduba o azotada (0, 37, 74 e 111 kg N ha-1), repartidos por quatro aplica es. A disponibilidade de azoto nítrico no solo, o comprimento radical e a concentra o de azoto nas folhas foram avaliados aos 33, 57, 96 e 127 dias após a planta o. A densidade radical (cm cm-3) sob o bolbo e a 4 cm da linha de cultura, nas diferentes datas e profundidades de amostragem, n o foi afectada pelos níveis de azoto. Ao longo ciclo, 65 a 100 % das raízes, em termos de comprimento radical, concentraram-se sob o bolbo e a densidade radical máxima alcan ada foi de 1,88 cm cm-3. A profundidade máxima de enraizamento situou-se entre os 20 e 30 cm, n o ultrapassando os 10 cm de profundidade até aos 32 dias após a planta o. Nas condi es do ensaio, os resultados indicam como recomendável uma aplica o de 30 kg ha- 1 de azoto à planta o e um aumento da quantidade de azoto aplicado (16,2% do total de N aplicado), no início da forma o do bolbo. A produ o comercial aumentou com o nível de azoto, mas as produ es obtidas com a aplica o de 74 kg ha-1 (5,12 kg m-2) e de 111 Kg N ha-1 (6,59 kg m-2) n o diferiram significativamente. Intermediate-day onions (cv. Gilmar) rooting patterns, soil availability NO3-, leaf N concentration and commercial yield were evaluated in a field trial where four nitrogen fertilizer rates (0, 37, 74 and 111 kg N ha-1) were applied into four split applications, following a randomized block design with four replications. Root length, soil availability NO3-, and leaf N concentration were evaluated at four dates during growing season (33, 57, 96 and 127 days after planting). Root length density (cm cm-3) at different sampling dates, locations (under the bulb and at 4 cm from the plant row) and depths was not affected by nitrogen level. For all sampling dates about 65 to 100 % of the root length was concentrated in the top 10 cm of the soil profile, under the bulb and the maximum root length density was 1.88 cm cm-3. The maximum rooting depth ranged from 20 and 30 cm, not exceeding 10 cm in depth, up to 32 days after planting. Under the conditions of
Influência do azoto no crescimento da cebola antes do inicio da forma o do bolbo Influence of nitrogen on onion growth before bulb initiation
Rui Manuel de Almeida Machado,Pedro Fraz?o Alpendre,Shakib Shahidian,Ricardo Azevedo Jesus
Revista de Ciências Agrárias , 2012,
Abstract: Este trabalho teve como objectivo estudar a influência da aplica o de azoto, em pré-planta o, em dois solos distintos, no crescimento aéreo e radical de cebolas de dia curto (cv. Minuetaka), entre a transplanta o e o início da forma o do bolbo. Para o efeito, realizou-se um ensaio em vasos com 10 tratamentos: dois solos (argilo-arenoso e arenoso) e cinco níveis de azoto (0, 10, 30, 40 e 50 kg de N ha-1) aplicados antes da planta o. O crescimento aéreo e radical da cebola, entre a transplanta o e o início da forma o do bolbo, n o foi influenciado pelo nível de azoto, nem pela interac o nível de azoto * tipo de solo. Assim, o azoto fornecido pelo solo (9 kg solo vaso-1), residual e proveniente da mineraliza o da matéria organica, mais o azoto inserido pela água de rega (20 mg N planta-1) foi suficiente para o crescimento das plantas antes do início da forma o do bolbo. O tipo de solo afectou significativamente o crescimento e a aloca o de matéria seca. A biomassa das plantas no solo argilo-arenoso foi 30 % superior à do arenoso, mas a biomassa das raízes, o comprimento radical total e específico e a aloca o de matéria seca nas raízes foram maiores no solo arenoso. O comprimento radical total das plantas no solo arenoso (43,74 m) foi 2,3 vezes superior ao do argilo-arenoso (19,26 m). The effect of nitrogen application prior transplanting on aboveground growth and root growth of the short- day onions (cv. Mineutaka), from transplanting to bulb initiation was studied in a pot experiment. The pot experiment was carried out with ten treatments, including two soil types (clay-sandy and sandy soil) and five levels of N application (0, 10, 30, 40 and 50 kg N ha-1) applied prior transplanting. Aboveground and root growth and biomass allocation (root: shoot ratio) were not significantly affected by nitrogen level or interaction nitrogen level * soil type. The residual soil inorganic N and the released N from organic matter, most nitrogen introduced by irrigation water (20 mg N plant-1), was sufficient for plant growth before bulb initiation. Plant growth and biomass allocation were significantly affected by soil type. Plant biomass in clay-sandy soil was 30% higher than in sandy soil. Total root length of plants grown in sandy soil (43.74 m) was 2.3 times higher than in clay-sandy soil (19.26 m). Root biomass, specific root length (SLR) and root-shoot ratio were higher in plants grown in sandy soil.
Using Data Mining with Time Series Data in Short-Term Stocks Prediction: A Literature Review  [PDF]
José Manuel Azevedo, Rui Almeida, Pedro Almeida
International Journal of Intelligence Science (IJIS) , 2012, DOI: 10.4236/ijis.2012.224023
Abstract: Data Mining (DM) methods are being increasingly used in prediction with time series data, in addition to traditional statistical approaches. This paper presents a literature review of the use of DM with time series data, focusing on shorttime stocks prediction. This is an area that has been attracting a great deal of attention from researchers in the field. The main contribution of this paper is to provide an outline of the use of DM with time series data, using mainly examples related with short-term stocks prediction. This is important to a better understanding of the field. Some of the main trends and open issues will also be introduced.
Evapotranspira??o máxima do tomateiro sob estufa plástica em fun??o de variáveis fenométricas e meteorológicas
Pivetta, Carina Rejane;Heldwein, Arno Bernardo;Tazzo, Ivonete Fátima;Maldaner, Ivan Carlos;Dalbianco, Leandro;Streck, Nereu Augusto;Machado, Rui Manuel Almeida;
Bragantia , 2011, DOI: 10.1590/S0006-87052011000300029
Abstract: the objective of this study was to estimate the maximum evapotranspiration (etm) of tomato inside greenhouse as a function of evaporation measured with "piche" evaporimeter exposed to solar radiation (epi) with and without easily measured meteorological and phenological variables during the 2005 spring growing season. daily etm (measured with drainage lysimeters), epi, air temperature, air vapor pressure deficit (d), leaf area index (lai), plant height (ph), and number of leaves (ln) were measured. models were fitted to estimate etm using data collected on even days of the experimental period. in the multiple regression analysis only models with parameters significant at 5% by t test and coefficient of determination (r2) greater than 0.85 were selected. models were evaluated with independent data collected on odd days of the period. statistics used for model evaluation were regression analyses between observed and estimated data, root mean square error (rmse), and accuracy (r), agreement (d) and confidence (c) indices. results showed that it is possible to estimate etm of tomato crop with acceptable accuracy (r2 between 0.87 e 0.92) to perform irrigation inside plastic greenhouse using models that take into account epi and at least one plant growth parameter; models with ph should be preferred. including d measured at 9 h in the models with epi and ln or ph or lai improved etm estimates.
Coronary-Subclavian Steal Syndrome: Percutaneous Approach
Carina Machado,Luís Raposo,Sílvio Leal,Pedro Araújo Gon?alves,Henrique Mesquita Gabriel,Rui Campante Teles,Manuel Sousa Almeida,Miguel Mendes
Case Reports in Cardiology , 2013, DOI: 10.1155/2013/757423
Abstract: Coronary subclavian steal syndrome is a rare ischemic cause in patients after myocardial revascularization surgery. Subclavian artery stenosis or compression proximal to the internal mammary artery graft is the underlying cause. The authors present a clinical case of a patient with previous history of non-ST elevation myocardial infarction, triple coronary bypass, and effort angina since the surgery, with a positive ischemic test. Coronary angiography revealed a significant stenosis of the left subclavian artery, proximal to the internal mammary graft. 1. Introduction The coronary subclavian steal syndrome (CSSS) was first described in 1974 and is caused by retrograde or insufficient blood flow through the internal mammary artery graft, with subsequent myocardial ischemia. Proximal atherosclerotic stenosis of the ipsilateral subclavian artery is the most frequent cause [1]. Although most cases of angina after coronary bypass graft surgery (CABG) are due to native-vessel or graft atherosclerotic disease progression, this syndrome should not be disregarded [2]. The traditional approach for this problem is surgical revascularization of the subclavian artery with a bypass graft, but percutaneous transluminal subclavian artery angioplasty has emerged as an effective alternative to surgery and it is now a widely accepted method of treating symptomatic subclavian steal syndrome. 2. Case Report The authors present the case report of a 69-year-old male patient with several cardiovascular risk factors (hypertension, hyperlipidaemia, and previous smoking) and history of coronary artery bypass grafting (CABG) 6 years before when the left internal mammary artery (LIMA) was grafted to the left anterior descending artery (LAD), saphenous vein conduit was grafted to posterior descendent artery and left radial artery grafted to the intermediary branch. No medical imaging of the aortic arch and its branches was performed before cardiac surgery. He had recurrence of angina following the surgery (CCS class II) mainly when exerting the upper limbs. His therapy was adjusted and remained only mildly symptomatic until 2011 when he was referred to for coronary angiography because of gradually worsening exertional angina with no response to medical therapy. There were no neurological or claudication complaints. Physical examination only showed an II/VI systolic murmur. Basal EKG and blood analysis were unremarkable. On the transthoracic echocardiogram, there was only mild aortic sclerosis and good global and segmental systolic left ventricle function. He had a positive exercise
Revasculariza??o do miocárdio: estudo comparativo do custo da cirurgia convencional e da angioplastia transluminal percutanea
Almeida, Rui Manuel Sequeira de;
Revista Brasileira de Cirurgia Cardiovascular , 2005, DOI: 10.1590/S0102-76382005000200009
Abstract: objective: to compare the cost of coronary bypass surgery (cbs) and percutaneous transluminal coronary angioplasty (ptca) for a one year follow-up. method: eight-six patients were submitted to 87 cbs and 240 patients to 267 ptca, between october 2003 and april 2004. the mean age of the two groups was 62 years. the cbs group was submitted to a mean of 3.7 bypass/ patient, using 96.5% of arterial conduits. in the ptca group, a mean of 1.1 angioplasties/procedure were performed. twenty-one (24.4%) patients had an angioplasty performed before the cbs. each group was subdivided in, group a and b, in respect to the manner of payment. results: the mean cost for cbs was r$ 7.759,78, per procedure; in the ptca group the cost/angioplasty was r$ 6.307,79. at the end of a year, the end values were r$ 7.875,73 for the cbs and r$ 8.234,96 for the ptca group. in group b the cbs patients had a mean hospital cost of r$ 11.061,63 and r$ 11.087,29 at the end of a year; in the ptca group the hospital costs were r$ 11.110,83, and at the end of a year r$ 13.414,59. conclusions: the author concludes that: 1) only 26.4% of the 326 patients were submitted to cbs; 2) ptca group presented 26.7% re-interventions/patient and cbs group only 3.5%; 3) cbs costs were 17.4% less than those of the ptca after one year, in group b.
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