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Acumulação de capital no Brasil sob a crise do fordismo: 1985-2002; Accumulation of capital in Brazil under Fordism crisis: 1985-2002

Schincariol, Vitor Eduardo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/11/2006 PT
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Esta dissertação ilustra como o regime fordista de acumulação brasileiro foi induzido à sua crise na década de oitenta, pelas políticas de ajuste econômico patrocinadas pelo FMI, e como na década seguinte a política de liberalização da economia terminou por reformatá-lo. Destacam-se as alterações estruturais na economia neste novo ambiente pós-fordista, e evidencia-se como este novo regime de acumulação não permitiu uma ampliação do produto e renda; This master dissertation elucidates how the Brazilian accumulation of fordist type was driven into its crisis in the eighties, by the adjustment policies of International Monetary Fund and how, during the nineties, the liberalization of economy put another one in curse, the so called post-fordist regime. The work approaches the structural changes of the Brazilian economy under this new post-fordist regime, and attempts to show how it was not able foster new economic growth, as expected

Dinâmica do acúmulo de forragem em pastos de Brachiaria brizantha cv. Marandu submetidos à lotação contínua e ritmos de crescimento contrastantes; Dynamics of herbage accumulation of marandu palisadegrass swards subjected to continuous stocking and contrasting rhythms of growth

Mesquita, Priscila de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/09/2008 PT
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Recentemente o conceito de alvo de manejo tem sido utilizado para definição de estratégias de manejo do pastejo, com a altura do pasto, dentre outras características estruturais do dossel, assumindo um papel importante para implementação desse conceito em condições de campo. Práticas de manejo podem influenciar de forma diferente os processos de crescimento e senescência, afetando assim a estrutura e o acúmulo de forragem e, por essa razão, precisam ter seu efeito conhecido de forma a permitir o planejamento práticas de manejo do pastejo eficientes e sustentáveis. Dentro desse contexto, o objetivo deste experimento foi avaliar a estrutura do dossel forrageiro, seus padrões de variação ao longo do ano e a dinâmica do acúmulo de forragem em pastos de capim-marandu mantidos a 30 cm de altura por meio de lotação contínua e submetidos a ritmos de crescimento contrastantes de janeiro de 2007 a abril de 2008. Os tratamentos corresponderam à aplicação de três doses de nitrogênio (150, 300 e 450 kg/ha de N) mais o controle (sem adubação), e foram alocados às unidades experimentais (piquetes de 1200 m2) segundo um delineamento de blocos completos casualizados, com quatro repetições. Foram avaliadas as seguintes variáveis-resposta: massa de forragem...

Dinâmica do crescimento e componentes do acúmulo de forragem de capim-elefante cv. Napier submetido a estratégias de pastejo rotativo; Dynamics of growth and components of herbage accumulation in elephant grass cv. Napier subjected to strategies of rotational stocking manament

Pereira, Lilian Elgalise Techio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 17/05/2013 PT
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A estrutura do dossel e o acúmulo de forragem resultam de processos integrados de adaptação às condições ambientais e de manejo vigentes que incluem desde o fluxo de tecidos em indivíduos na comunidade vegetal até padrões de adaptação em nível de população de plantas. Baseado na hipótese de que estratégias de pastejo rotativo modificam as relações entre indivíduos da comunidade vegetal e alteram a proporção entre classes de perfilhos com consequências sobre a dinâmica dos processos morfogênicos e componentes do acúmulo de forragem do dossel o objetivo deste trabalho foi avaliar como estão integradas as respostas morfogênicas e as características estruturais de perfilhos basais e aéreos ao longo da rebrotação e seu reflexo sobre o acúmulo de forragem e estrutura do dossel de capim-elefante cv. Napier de janeiro de 2011 a abril de 2012. Os tratamentos corresponderam a combinações entre duas condições pós- (alturas pós-pastejo de 35 e 45 cm) e duas condições pré-pastejo (95% e máxima interceptação de luz - IL95% e ILMáx) e foram alocados às unidades experimentais (piquetes de 850 m2) segundo arranjo fatorial 2x2 e delineamento de blocos completos casualizados, com quatro repetições. Estratégias distintas de crescimento foram utilizadas pelo capim-elefante cv. Napier em resposta às metas de IL pré-pastejo. Estas foram caracterizadas por mudança na proporção e população das diferentes classes de perfilhos ilustrada pela maior relação aéreos/(basais+vasos condutores) nos pastos manejados com a meta ILMáx. A maior competição por recursos luminosos...

Interceptação luminosa, massa de raízes e acúmulo de forragem em Arachis pintoi cv. Belmonte submetido a intensidades de pastejo; Light interception, root mass and herbage accumulation in Arachis pintoi cv. Belmonte subjected to intensities of grazing

Carvalho, Lucas da Rocha
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/02/2014 PT
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Atualmente, o termo sustentabilidade vem ganhando destaque dentro das atividades agrícolas e para a produção animal em pastagens não é diferente. As leguminosas forrageiras são conhecidas por algumas características peculiares como grande capacidade de fixação do nitrogênio atmosférico e elevado valor nutritivo, surgindo assim como uma alternativa viável nesse novo modelo de produção. Entretanto, muitas vezes práticas de manejo inadequadas acabam não permitindo a exploração do potencial dessas espécies, levando-as ao desuso. Dessa forma, conhecer a resposta de plantas (alterações em forma e função) a intensidades de pastejo é imprescindível para permitir a idealização de estratégias de manejo eficientes que possam contribuir para a otimização do processo produtivo em sistemas pastoris. Este trabalho fez parte de uma série de experimentos delineados com o propósito de avaliar aspectos gerais de crescimento e desenvolvimento do amendoim forrageiro sob pastejo e suas implicações sobre a produção de forragem e potencial de consumo pelos animais. Seu objetivo específico foi avaliar as características produtivas de Arachis pintoi cv. Belmonte submetido a intensidades de pastejo sob lotação contínua. O experimento foi conduzido na Escola Superior de Agricultura "Luiz de Queiroz"...

Características estruturais do dossel forrageiro e acúmulo de forragem de Brachiaria brizantha cv. Piatã submetido a regime de sombra em sistemas de integração lavoura pecuária floresta; Sward structural characteristics and herbage accumulation in Brachiaria brizantha cv. Piatã subjected to shade regimes in a crop-livestock-forest integration area

Mascheroni, Jorge Daniel Caballero
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/02/2015 PT
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Sistemas integrados têm sido apontados como alternativas ecologicamente apropriadas para recuperar a produtividade de pastagens tropicais degradadas, gerando benefícios tanto para o meio ambiente como para os animais. Apesar das diversas vantagens atribuídas aos sistemas integrados, existem ainda limitações técnicas que dificultam a otimização do processo produtivo, função da natureza complexa e multidisciplinar das interações entre seus componentes bióticos e abióticos. Existem, portanto, aspectos importantes que podem comprometer a produtividade do sistema, entre eles, as alterações na estrutura do dossel forrageiro e a menor produção de forragem, principalmente pela diminuição da radiação luminosa que chega ao sub-bosque. Partindo da hipótese que o dossel arbóreo irá determinar a quantidade e a qualidade de luz disponível para o sub-bosque e, assim, influenciar a estrutura do dossel forrageiro e a produção de forragem do capim-piatã manejado sob pastejo rotativo utilizando metas de interceptação luminosa (IL) prépastejo, o objetivo deste trabalho foi avaliar as características estruturais e o acúmulo de forragem de Brachiaria brizantha cv Piatã em sistema ILPF de dezembro de 2013 a julho de 2014. O estudo foi desenvolvido por meio de três experimentos realizados de forma concomitante para avaliar três regimes de luz: (1) capim-piatã cultivado em área livre de árvores (pleno sol; PS); (2) sombreamento gerado por meio de fileiras duplas de Eucalipto nas bordaduras dos piquetes (S1); e (3) sombreamento gerado por meio de quatro renques de fileiras triplas de Eucalipto dispostos dentro dos piquetes de forma alternada com porções de pasto (S2). Os regimes de luz S1 e S2 foram divididos em duas faixas de sombra (central e lateral) para descrição da variação da luz dentro dos piquetes e sua implicação sobre o padrão de crescimento das plantas. O período experimental foi dividido em três períodos de avaliação em função do índice pluviométrico registrado. Para estudar a influência das árvores sobre a medição de IL e sua implicação sobre o crescimento das plantas...

Cathodic stripping voltammetric determination of ceftazidime with reactive accumulation at a poly-L-lysine modified hanging mercury drop electrode

Ferreira, V. S.; Zanoni, Maria Valnice Boldrin; Fogg, A. G.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 159-166
ENG
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Ceftazidime is hydrolysed only slowly at pH 10 at room temperature. This is indicated by a small cathodic stripping voltammetric peak obtained at pH 10 at a hanging mercury drop electrode at about -0.6 V which corresponds to the reduction of the hydrolysis product. This peak is enhanced more than tenfold by the addition of poly-L-lysine (PLL) to the electrolyte solution. The optimum accumulation potential is between 0 and -0.1 V: the size of the peak decreases steadily, however, as the accumulation potential is moved to more negative potentials and is about one-sixth the size for accumulation at -0.4 V. Existing knowledge of the organic chemistry of cephalosporins indicates that the accumulation must involve an aminolysis reaction of the unprotonated PLL with the beta-lactam ring of the ceftazidime. The limit of detection (3 sigma) in standard solutions was calculated to be 1 x 10(-10) mol l(-1). The detection limit in buffer solution containing 1% of urine was calculated to be 5 x 10(-9) mol l(-1), i.e. 5 x 10(-6) mol l(-1) in the urine. (C) 1999 Elsevier B.V. B.V. AU rights reserved.

Moderate physical activity from childhood contributes to metabolic health and reduces hepatic fat accumulation in adult rats

De Moura, Leandro Pereira; Da Silva Sponton, Amanda Christine; De Araújo, Michel Barbosa; Dalia, Rodrigo Augusto; Pauli, José Rodrigo; De Mello, Maria Alice Rostom
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
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Background: Obesity, oxidative stress and inflammation, by triggering insulin resistance, may contribute to the accumulation of hepatic fat, and this accumulation by lipotoxicity can lead the organ to fail. Because obesity is growing at an alarming rate and, worryingly, in a precocious way, the present study aimed to investigate the effects of moderate physical training performed from childhood to adulthood on liver fat metabolism in rats. Methods. Twenty rats that were 28days old were divided into two groups: control (C) and trained (T). The C Group was kept in cages without exercise, and the T group was submitted to swimming exercise for 1hour/day, 5days/week from 28 to 90days of age (8weeks) at 80% of the anaerobic threshold determined by the lactate minimum test. At the end of the experiment, the body weight gain, insulin sensitivity (glucose disappearance rate during the insulin tolerance test), concentrations of free fatty acids (FFA) and triglycerides (TG) and hepatic lipogenic rate were analyzed. For the statistical analysis, the Student t-test was used with the level of significance preset at 5%. Results: The T group showed lower body weight gain, FFA concentrations, fat accumulation, hepatic lipogenic rate and insulin resistance. Conclusion: The regular practice of moderate physical exercise from childhood can contribute to the reduction of obesity and insulin resistance and help prevent the development of accumulation of hepatic fat in adulthood. © 2013de Moura et al; licensee BioMed Central Ltd.

Relationship between Distance to Flow Accumulation Lines and Spatial Variability of Irrigated Maize Grain Yield and Moisture Content at Harvest

Marques da Silva, José Rafael; Silva, Luis Leopoldo
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: 6848 bytes; application/pdf
ENG
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Analysis of yield variability factors is an important issue in order to obtain information that allows the delineation of areas with stable yield patterns for application of precision agriculture techniques. The objective of this study was to evaluate the spatial and temporal variability of yield and grain moisture content at harvest with their distance to flow accumulation lines, based on 3-yr data of centre-pivot irrigated maize crop in Southern Portugal. Yield data were collected over the period from 2002 to 2004 and divided into data sets relating to nine classes of distances to flow accumulation lines. Based on these data sets, the relation between yield and grain moisture content at harvest with distance to flow accumulation lines was analysed. Results show that there is an increase in yield with the decrease of distance to flow accumulation lines, both in years with normal or above-normal applied irrigation water. In situations where insufficient irrigation water was applied, grain moisture content at harvest shows an increase as distance to flow accumulation lines decreases, but in years in which more irrigation water was applied, less grain moisture content at harvest near the flow accumulation lines was observed.

Distance to flow accumulation lines (DFL) and its relationship with other yield-affecting factors

Marques da Silva, José Rafael; Silva, Luis Leopoldo; Coelho, Renato
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Conferência ou Objeto de Conferência
POR
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Topography and field hydrological parameters can be used to explain yield spatial variability. One of these parameters is distance to flow accumulation lines (DFL). Previous works showed that yield of irrigated maize in situations of undulated topography has a significant relationship with DFL. The objective of this study was to analyze soil, landscape and plant factors considering their interaction with distance to flow accumulation lines, and verify their influence on yield variability. Different soil parameters (depth, texture, organic matter, hydraulic conductivity, water content) were determined on nine survey areas with different distances to flow accumulation lines. Leaf stomatal conductance was also measured at these areas. Soil depth was the parameter with the most significant interaction with DFL. This suggests that, in the studied conditions, a higher soil depth near flow accumulation lines, allowing a higher volume for root development and retrieving of soil water and nutrients, was the most important factor influencing yield.

Phytomass production and nutrient accumulation by green manure species

Mangaravite,José Carlos Soares; Passos,Renato Ribeiro; Andrade,Felipe Vaz; Burak,Diego Lang; Mendonça,Eduardo de Sá
Fonte: Universidade Federal de Viçosa Publicador: Universidade Federal de Viçosa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 EN
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Green manuring is recognized as a viable alternative to improve nutrient cycling in soils. The aim of this study was to evaluate the phytomass production and nutrient accumulation in shoots of the summer green manures jack bean [Canavalia ensiformis (L.) DC.], dwarf pigeon pea (Cajanus cajanvar var. Flavus DC.), dwarf mucuna [Mucuna deeringiana (Bort) Merr] and sunn hemp (Crotalaria juncea L.), under nitrogen fertilization and/or inoculation with N-fixing bacteria. A split plot design was arranged with the four Fabaceae species as main plots and nitrogen fertilization (with and without) and inoculation with diazotrophic bacteria (with and without) as the subplots, in a 2² factorial. The experiment was arranged as a randomized complete block design with four replications. In the conditions of this trial, the sunn hemp had the highest production of shoot phytomass (12.4 Mg ha-1) and nutrient accumulation, while the dwarf mucuna had the lowest production of shoot phytomass (3.9 Mg ha-1) and nutrient accumulation. The results showed no effect of nitrogen fertilization or inoculation with N-fixing bacteria on the production of shoot phytomass and nutrient accumulation, except for inoculation without nitrogen fertilization...

Effects of the physiological age of seed potatoes on tuber initiation and starch and dry matter accumulation.

CALDIZ, D.O.; BROCCHI, G.; ALANIZ, J.; MARCHAN, C.
Fonte: Pesquisa Agropecuaria Brasileira, Brasilia, v.31, n.12, p.853-858, dez. 1996. Publicador: Pesquisa Agropecuaria Brasileira, Brasilia, v.31, n.12, p.853-858, dez. 1996.
Tipo: Artigo em periódico indexado (ALICE)
EN
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The physiological age of seed potato tubers (Solanum tuberosum L.) modifies several morphological, physiological and agronomic characteristics of the crop. However, there is little evidence on the possible influence of physiological age upon the mechanism involved in tuber initiation and starch accumulation. This study investigated the effects of the physiological age of seed tubers on tuber initiation, starch synthase activity and dry matter accumulation and distribution. Physiologically aged seed potatoes promoted an early tuber initiation in the following crop. Early in the season the stolon tips of these plants showed an increase in starch synthase activity and an anticipated starch accumulation. During the rest of the season the starch synthase activity in the stolon tips of tubers grown from young seed was higher than those grown from the physiologically older ones, which decreased by day 70 after planting. Dry matter accumulation by leaves and stems did not differ between treatments, while tuber dry matter accumlation was higher in those plants originated from physiologically young tubers. These results confirmed that physiologically old seed anticipates tuber initiation and demonstrated that the pattern of starch synthase activity...

Acute toxicity, accumulation and tissue distribution of copper in the blue crab Callinectes sapidus acclimated to different salinities: In vivo and in vitro studies

Martins, Camila De Martinez Gaspar; Barcarolli, Indianara Fernanda; Menezes, Eliana Jaime de; Giacomin, Marina Mussoi; Wood, Chris; Bianchini, Adalto
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
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In vivo and in vitro studies were performed to evaluate acute toxicity, organ-specific distribution, and tissue accumulation of copper in Callinectes sapidus acclimated to two different experimental salinities (2 and 30 ppt). Blue crabs were quite tolerant to copper. Acute dissolved copper toxicity (96-h LC50 and its corresponding 95% confident interval) was higher at salinity 2 ppt (5.3 (3.50–8.05)_M Cu) than at 30 ppt (53.0 (27.39–102.52)_M Cu). The difference between salinities can be completely explained based on the water chemistry because it disappeared when 96-h LC50 values were expressed as the free Cu2+ ion (3.1 (1.93–4.95)_M free Cu at 2 ppt versus 5.6 (2.33–13.37)_M free Cu at 30 ppt) or the Cu2+ activity (1.4 (0.88–2.26)_M Cu activity at 2 ppt versus 1.7 (0.71–4.07)_M Cu activity at 30 ppt). The relationships between gill Cu burden and % mortality were very similar at 2 and 30 ppt, in accord with the Biotic Ligand Model. In vivo experiments showed that copper concentration in the hemolymph is not dependent on metal concentration in the surrounding medium at either experimental salinity. They also showed that copper flux into the gills is higher than into other tissues analyzed, and that anterior and posterior gills are similarly important sites of copper accumulation at both experimental salinities. In vitro experiments with isolated-perfused gills showed that there is a positive relationship between copper accumulation in this tissue and the metal concentration in the incubation media for both anterior and posterior gills. A similar result was observed at both low and high salinities. Furthermore...

Mechanisms of copper accumulation in isolated mantle cells of the marine clam Mesodesma mactroides

Lopes, Thaís Martins; Barcarolli, Indianara Fernanda; Oliveira, Camila Bento de; Souza, Marta Marques de; Bianchini, Adalto
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
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In vivo copper accumulation was determined in tissues (mantle, gills, digestive gland, and hemolymph) following exposure to Cu (5mM) for up to 96 h. Mantle was the tissue that accumulated the most Cu, followed by gill, digestive gland, and hemolymph. Therefore, in vitro Cu accumulation was evaluated in isolated mantle cells exposed to 0.5, 1.0, 2.5, and 5.0mM Cu for 1 and 3 h. After both exposure times, no change in cell viability was observed. However, a significant Cu accumulation was observed in cells exposed to 2.5 and 5.0mMCu. Cell exposure to 2.5 mMCu for 1 h did not affect the ionic (Na þ , K þ , Ca2þ , and Cl_) content of isolated mantle cells, characterizing an ‘‘ideal’’ noneffect concentration for the study of the involvement of different ion-transporting proteins (Na þ , K þ , and Cl _ channels; Na þ /K þ 2Cl _ and Na þ /Cl _ cotransporters; Na þ /Ca2þ , Cl _ /HCO_ 3 , and Na þ /H þ exchangers; Na þ /K þ -ATPase; VATPase; and carbonic anhydrase) in Cu accumulation. Isolated cells were pre-exposed (30 min) to specific blockers or inhibitors of the ion-transporting proteins and then exposed (1 h) to Cu (2.5 mM) in the presence of the drug. A significant increase of 29.1 and 24.3% in Cu accumulation was observed after cell incubation with acetozalamide (carbonic anhydrase inhibitor) and NPPB (Cl _ channels blocker)...

Undervaluation through Foreign Reserve Accumulation : Static Losses, Dynamic Gains

Korinek, Anton; Servén, Luis
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
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This paper shows that real exchange rate undervaluation through the accumulation of foreign reserves may improve welfare in economies with learning-by-investing externalities that arise disproportionately from the tradable sector. In the presence of targeting problems or when policy choices are restricted by multilateral agreements, first-best policies such as subsidies to capital accumulation, or subsidies to tradable production are not feasible. A neo-mercantilist policy of foreign reserve accumulation "outsources" the targeting problem or overcomes the multilateral restrictions by providing loans to foreigners that can only be used to buy up domestic tradable goods. This raises the relative price of tradable versus non-tradable goods (i.e. undervalues the real exchange rate) at the static cost of temporarily reducing tradable absorption in the domestic economy. However, since the tradable sector generates greater learning-by-investing externalities, it leads to dynamic gains in the form of higher growth. The net welfare effects of reserve accumulation depend on the balance between the static losses from lower tradable absorption versus the dynamic gains from higher growth.

Dinuclear polypyridylruthenium(II) complexes: Flow cytometry studies of their accumulation in bacteria and the effect on the bacterial membrane

Li, F.; Feterl, M.; Warner, J.; Keene, F.; Collins, J.
Fonte: Oxford Univ Press Publicador: Oxford Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
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Objectives To determine the energy dependency of and the contribution of the membrane potential to the cellular accumulation of the dinuclear complexes [{Ru(phen)₂}₂{μ-bbn}]⁵+ (Rubbn) and the mononuclear complexes [Ru(Me₄phen)₃]²+ and [Ru(phen)₂(bb₇)]²+ in Staphylococcus aureus and Escherichia coli, and to examine their effect on the bacterial membrane. Methods The accumulation of the ruthenium complexes in bacteria was determined using flow cytometry at a range of temperatures. The cellular accumulation of the ruthenium complexes was also determined in cells that had been incubated with the metal complexes in the presence or absence of metabolic stimulators or inhibitors and/or commercial dyes to determine the membrane potential or membrane permeability. Results The accumulation of ruthenium complexes in the two bacterial strains was shown to increase with increasing incubation temperature, with the relative increase in accumulation greater with E. coli, particularly for Rubb₁₂ and Rubb₁₆. No decrease in accumulation was observed for Rubb₁₂ in ATP-inhibited cells. While carbonyl cyanide m-chlorophenyl hydrazone (CCCP) did depolarize the cell membrane, no reduction in the accumulation of Rubb₁₂ was observed; however...

New Product Technology, Accumulation, and Growth

Khan, Faruk A.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH
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This paper asks whether new technological capacity for producing and exporting additional products provides incentives for greater capital accumulation, without being fully reflected in a higher rate of total factor productivity (TFP) growth. Using a highly disaggregated data set of each country's trade flows into the United States, the author constructs a direct and independent measure of technological improvements for each country over time based on the number of new product varieties exported to the United States. The author shows, in a panel data setting, that acquiring the technological capacity for producing new products stimulates more rapid capital accumulation in developing countries, even after holding fixed the rate of TFP growth. His findings provide evidence against the alternative view that technological improvements are essentially unimportant: a view based on the findings of Young (1995) and others that instances of spectacular economic growth have been associated with unspectacular rates of TFP growth. The author provides a model to show how an expansion in the technological capacity for producing additional products can lead to more rapid factor accumulation, without necessarily improving measured TFP. His findings suggest that while rapid accumulation of physical and human capital may have characterized the East Asian growth experience...

SLUDGE ACCUMULATION AND CHARACTERIZATION IN DECENTRALIZED COMMUNITY WASTEWATER TREATMENT SYSTEMS WITH PRIMARY CLARIFIER TANKS AT EACH RESIDENCE

LOSSING, HEATHER
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 11326514 bytes; application/pdf
EN; EN
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Sludge accumulation, treatment and disposal can represent a high percentage of the operating cost for a wastewater system. This is especially important for small-scale and onsite wastewater treatment systems, where sludge removal can be one of the few operating costs of the system. In 2000, as a result of a large number of septic system failures, the community of Wardsville installed a Clearford Industries Inc. Small Bore Sewer™ (SBS™) system which included two-chamber 3600 L tanks located on the properties of individual homes. The tanks were collectively attached to a small bore piping system to deliver the effluent from the tanks to a small community wastewater treatment system. During the summer of 2007, a field study was initiated with a community survey, followed by a review of candidate sites, leading to the selection of 29 sites for site investigation and sampling. Sampling involved the collection of samples for sludge characterization along with the measurements of the height of solids (scum and sludge) within the tank. The data were analyzed to determine the factors having a statistically significant impact on solids accumulation rates within each of the two chambers of the tank. Household water usage was found to be the variable having the strongest association with sludge and scum accumulation...

SLUDGE ACCUMULATION AND CHARACTERIZATION IN DECENTRALIZED COMMUNITY WASTEWATER TREATMENT SYSTEMS WITH PRIMARY CLARIFIER TANKS AT EACH RESIDENCE

LOSSING, HEATHER
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 11326514 bytes; application/pdf
EN; EN
Relevância na Pesquisa
36.32%
Sludge accumulation, treatment and disposal can represent a high percentage of the operating cost for a wastewater system. This is especially important for small-scale and onsite wastewater treatment systems, where sludge removal can be one of the few operating costs of the system. In 2000, as a result of a large number of septic system failures, the community of Wardsville installed a Clearford Industries Inc. Small Bore Sewer™ (SBS™) system which included two-chamber 3600 L tanks located on the properties of individual homes. The tanks were collectively attached to a small bore piping system to deliver the effluent from the tanks to a small community wastewater treatment system. During the summer of 2007, a field study was initiated with a community survey, followed by a review of candidate sites, leading to the selection of 29 sites for site investigation and sampling. Sampling involved the collection of samples for sludge characterization along with the measurements of the height of solids (scum and sludge) within the tank. The data were analyzed to determine the factors having a statistically significant impact on solids accumulation rates within each of the two chambers of the tank. Household water usage was found to be the variable having the strongest association with sludge and scum accumulation...

Sediments Of Southern Lake Huron: Elemental Composition And Accumulation Rates

Robbins, John A.
Fonte: Universidade de Delaware Publicador: Universidade de Delaware
Tipo: Relatório Formato: 17070461 bytes; application/pdf
EN_US
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It is widely recognized that most metal contaminants in lakes are primarily associated with particulate matter and are conveyed to underlying deposits in association with fine-grained materials such as organic debris, hydroxides of iron, and manganese or clay minerals. In the Great Lakes the fine-grained sediments and associated contaminants are not deposited uniformly over the bottom but are confined to "pockets" or depositional basins which are of more limited extent and generally found in deeper areas of each lake. This report is the first in a series of three comprehensive reports which describes the composition and rates of accumulation of metal contaminants in the depositional basins of Lake Huron. This first report deals with the two principal depositional basins in southern Lake Huron: the Port Huron basin and the Goderich basin. Over a period of a year (1974-1975) nearly 100 sediment cores were taken within these two basins. Cores were carefully sectioned aboard ship and subsequently analyzed for large number of elements using state-of-the-art methods. Elements determined include Al, As, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Eu, Fe, K, La, Lu, Hg, Hf, Mg, Mo, Mn, Na, Ni, P, Pb, Rb, Sb, Sc, Si, Sm,Sn, Sr, Ti, Th...

Determination of vanadium accumulation in onion root cells (Allium cep a L.) and its correlation with toxicity

Marcano,Letty; Carruyo,Ingrid; Fernández,Yusmary; Montiel,Xiomara; Torrealba,Zaida
Fonte: Biocell Publicador: Biocell
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2006 EN
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The vanadium is a metal that presents great interest from the toxicological point of view, because of the numerous alterations that can take place in different biological systems. This work evaluated the capacity of vanadium accumulation and its correlation with genotoxic effects in root cells of Allium cepa L. The bulbs were cultivated in renovated filtered water each 24 h, at a temperature of 25 ± 0.5 ° C, in darkness and constant aeration. Treatments were carried out under the same experimental conditions, using water solutions of vanadium of 25, 50, 75 and 100 µ g/g for 0, 12, 24, 48 and 72 h. A control was carried out where metal solution was substituted by distilled water. After the treatment, the meristems were fixed with alcohol - acetic acid (3:1) and stained according to the technique of Feulgen. The capacity of accumulation was determined by GFAAS. The analysis of the results revealed an accumulation of the metal for all times and concentrations. No correlation was presented among vanadium accumulation, growth and mitotic index; however, positive correlation was given with the induction of chromosomic aberrations. In conclusion, vanadium is able to induce cytotoxic effect in the exposed roots, but only genotoxic effect was correlated with metal accumulation.