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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

Enriquecimento com Campomanesia phaea (Berg.) Landr. e Euterpe edulis Martius em fragmentos de floresta ombrófila densa em estádio secundário

Souza, Luana Santos de [UNESP] 02 September 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-02Bitstream added on 2014-06-13T19:00:12Z : No. of bitstreams: 1 souza_ls_me_botfca.pdf: 961679 bytes, checksum: 5d77257a709f3b2afe664e245053299b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Apesar da crescente preocupação com o bioma Mata Atlântica, no âmbito nacional e internacional, poucas medidas efetivas têm sido tomadas para a preservação e recuperação dessas áreas. Como resultado, ocorre a extinção local de espécies, principalmente aquelas mais sensíveis a distúrbios e que sofram pressão adicional do seu uso pela população. Este é o caso do cambuci (Campomanesia phaea (Berg.) Landr.) e do palmito-juçara (Euterpe edulis Martius). O presente trabalho teve por objetivo avaliar o desenvolvimento dessas espécies nativas através do sistema de enriquecimento em remanescentes florestais. As questões respondidas foram: As espécies são aptas ao enriquecimento em fragmentos de diferentes estágios sucessionais? Os fragmentos apresentam diferenças nas variáveis microclimáticas? O estudo foi realizado em dois fragmentos de Floresta Ombrófila Densa (floresta secundária de porte arbóreo baixo densa (FSPABD) e floresta secundária de porte arbóreo médio densa (FSPAMD)), para ambas as espécies. O delineamento experimental adotado foi o fatorial 2 x 2 (2 espécies x 2 fragmentos), em blocos casualizados, com seis repetições, ou seja, seis blocos. Altura da parte aérea e diâmetro do coleto de cada espécie foram mensurados a cada 60 dias, aproximadamente, e temperatura mínima e máxima, umidade mínima e máxima do ar, temperatura mínima e máxima do solo e intensidade relativa de luz foram mensuradas em 3 estações do ano (primavera, verão, outono), em cada parcela experimental. Os dados mensurados foram comparados por meio de análise de variância e teste de Tukey a 5% de probabilidade. Os dados de sobrevivência (taxa de sobrevivência por período) foram submetidos à análise de sobrevivência através do estimador de Kaplan-Meier... / Despite the growing society’s concern about the Atlantic Rain Forest biome, nationally or internationally, few effective measures have been taken for the preservation and rehabilitation of these areas. The result has been species loss, especially those more sensitive to disturbances and prone to additional pressure for their use by the population. This is the case of cambuci (Campomanesia phaea (Berg.) Landr.) and juçara- palm (Euterpe edulis Martius). This study aimed at evaluating the development of these native species in enrichment planting systems in forest remnants. The questions to be answered where: are the species suitable to plant enrichment in two tropical rainforest fragments? Do fragments have different microclimatic variables? The study was conducted in two fragments, low height dense secondary forest (LHDSF) and medium height dense secondary forest (MHDSF). The experimental design was factorial 2 x 2 (2 species x 2 fragments), in randomized blocks with six replicates. Data on minimum and maximum temperature and minimum and maximum air relative humidity, minimum and maximum soil temperature and relative light intensity index were rated in three seasons (spring, summer, autumn). The initial seedlings growth and physical data were evaluated periodically and the results were compared using variances analysis and post hoc Tukey test. Although most physical data collected differed between areas, seedling height and stem diameter of each species did not differ at 5% level between areas (LHDSF and MHDSF) in most assessments. The palm-tree (46 % in LHDSF and 93,6 % in MHDSF) had a higher survivorship rate than the cambuci (46 % in LHDSF and 50 % in MHDSF), showing a higher adaptation in enrichment plantings. The cambuci needs more studies in different... (Complete abstract click electronic access below)
342

The Effects of a Partially Structured Christian Marriage Enrichment Program Upon Marital Communication, General Marital Adjustment, and Purpose in Life

Wilson, Douglas A. 05 1900 (has links)
The problem of this study was the negative or positive effects of a partially structured Christian marriage enrichment weekend upon marital communication, marital adjustment, and purpose in life. The results indicated that on all four tests both groups improved significantly over a two-month period but not over a one-week period. The general conclusions to be drawn are two-fold. First, a partially structured Christian marriage enrichment weekend, namely Enjoying Marriage, will probably help a couple improve in communication, adjustment, and purpose in life. Second, only on adjustment and purpose in life can one say that such improvement is based specifically upon the content of the weekend. The reason for this is that a weekend retreat group who received no treatment on marriage also improved in communication and on one specific type of marital adjustment as measured by the Polyfactor Sentence Completion Survey.
343

Meta-analyses on studies about the identification and attention of the gifted and talented in Peru / Meta-análisis sobre estudios de identificación y atención al talento y la superdotación en el Perú

Blumen, Sheyla 25 September 2017 (has links)
Are gifted and talented identification programs scientifically based, fair and unbiased? Aregifted enrichment programs effective? Financia! pressures from NGOs and prívate founda­ tions, changes in national educational policies, as well as multicultural issues, are forcing psychologists and educators to face these questions. Our review discusses the important changes that have begun to alter the gifted and talented field in Latin America, especially in Peru. It describes recent empirical studies in multicultural populations and analyses the impact of the intervention programs, both, on the teacher training leve! as well as on thegifted enrichment programs,  which are being developed in the region. / ¿Tienen los programas de identificación del talento y la superdotación bases científicas sólidas, justas e imparciales? ¿Son los programas de intervención para talentosos y superdotados efectivos? Las presiones financieras que ejercen las fundaciones que brindan apoyo económico, los cambios recientes en las leyes, así como las consideraciones respecto a la multiculturalidad están forzando a los psicólogos y educadores alrededor del mundo a confrontar estos cuestionamientos. La presente revisión discute los cambios que han empezado a alterar este campo de estudio en América Latina y en especial en el Perú. Se presenta un análisis de estudios empíricos en poblaciones multiculturales, así como una reflexión sobre el impacto de los programas de intervención, a nivel de capacitación docente y de enriquecimiento cognitivo/afectivo, que se desarrollan en la región.
344

Microbial Electrochemical Cells for Selective Enrichment and Characterization of Photosynthetic and Haloalkaliphilic Anode-Respiring Bacteria

January 2013 (has links)
abstract: Microbial electrochemical cells (MXCs) are promising platforms for bioenergy production from renewable resources. In these systems, specialized anode-respiring bacteria (ARB) deliver electrons from oxidation of organic substrates to the anode of an MXC. While much progress has been made in understanding the microbiology, physiology, and electrochemistry of well-studied model ARB such as Geobacter and Shewanella, tremendous potential exists for MXCs as microbiological platforms for exploring novel ARB. This dissertation introduces approaches for selective enrichment and characterization of phototrophic, halophilic, and alkaliphilic ARB. An enrichment scheme based on manipulation of poised anode potential, light, and nutrient availability led to current generation that responded negatively to light. Analysis of phototrophically enriched communities suggested essential roles for green sulfur bacteria and halophilic ARB in electricity generation. Reconstruction of light-responsive current generation could be successfully achieved using cocultures of anode-respiring Geobacter and phototrophic Chlorobium isolated from the MXC enrichments. Experiments lacking exogenously supplied organic electron donors indicated that Geobacter could produce a measurable current from stored photosynthate in the dark. Community analysis of phototrophic enrichments also identified members of the novel genus Geoalkalibacter as potential ARB. Electrochemical characterization of two haloalkaliphilic, non-phototrophic Geoalkalibacter spp. showed that these bacteria were in fact capable of producing high current densities (4-8 A/m2) and using higher organic substrates under saline or alkaline conditions. The success of these selective enrichment approaches and community analyses in identifying and understanding novel ARB capabilities invites further use of MXCs as robust platforms for fundamental microbiological investigations. / Dissertation/Thesis / Ph.D. Microbiology 2013
345

Niche Differentiation of Ammonia-Oxidizing Microbial Communities in Arid Land Soils

January 2013 (has links)
abstract: Human activity has increased loading of reactive nitrogen (N) in the environment, with important and often deleterious impacts on biodiversity, climate, and human health. Since the fate of N in the ecosystem is mainly controlled by microorganisms, understanding the factors that shape microbial communities becomes relevant and urgent. In arid land soils, these microbial communities and factors are not well understood. I aimed to study the role of N cycling microbes, such as the ammonia-oxidizing bacteria (AOB), the recently discovered ammonia-oxidizing archaea (AOA), and various fungal groups, in soils of arid lands. I also tested if niche differentiation among microbial populations is a driver of differential biogeochemical outcomes. I found that N cycling microbial communities in arid lands are structured by environmental factors to a stronger degree than what is generally observed in mesic systems. For example, in biological soil crusts, temperature selected for AOA in warmer deserts and for AOB in colder deserts. Land-use change also affects niche differentiation, with fungi being the major agents of N2O production in natural arid lands, whereas emissions could be attributed to bacteria in mesic urban lawns. By contrast, NO3- production in the native desert and managed soils was mainly controlled by autotrophic microbes (i.e., AOB and AOA) rather than by heterotrophic fungi. I could also determine that AOA surprisingly responded positively to inorganic N availability in both short (one month) and long-term (seven years) experimental manipulations in an arid land soil, while environmental N enrichment in other ecosystem types is known to favor AOB over AOA. This work improves our predictions of ecosystem response to anthropogenic N increase and shows that paradigms derived from mesic systems are not always applicable to arid lands. My dissertation also highlights the unique ecology of ammonia oxidizers and draws attention to the importance of N cycling in desert soils. / Dissertation/Thesis / Ph.D. Biology 2013
346

Investigating developmental effects in and-enrichment

Högberg, Hanna January 2005 (has links)
Two propositions connected by and have the same truth-value, irrespective of the order of the conjuncts. However, in a sentence like “I put my socks and shoes on” it becomes obvious that the order of the conjuncts affects the meaning of the sentence. This study concerns the contribution of pragmatics to and by implicit enrichment to and then or and thus. It includes three experiments that investigate and-enrichment in adults and children. Nine five-line stories concerning everyday events were used. After each story the participants were to respond “yes” or “no” to a statement which referred to two events that occurred in the story, conjoined with and. In the critical statement, the two events were presented in the inverse order to which they had occurred. The results show no general developmental effect but awareness of the task plays a critical role for and-enrichment production. Ten-year-olds enrich and to the same extent as adults when no efforts are made to mask the intention behind the task. However, when a more spontaneous response is captured by masking the purpose of the task children respond more logically. There are no clear evidence that and-enrichment is affected by the cognitive demands of the task.
347

Obtenção de leveduras vivas enriquecidas para suplementação nutricional e probiótico / Enriched live yeasts for nutritional supplementation and pro-biotic.

André Eduardo de Souza Belluco 14 May 2008 (has links)
A presente pesquisa visou o acúmulo dos micronutrientes ferro e zinco em levedura da espécie Saccharomyces cerevisiae, em meio contendo 300 mg L-1 de ferro ou zinco (previamente definido) de acordo com o respectivo experimento. Ainda, teve o intuito de adicionar a levedura viva em um substrato (milho), esterilizado por irradiação gama (dose previamente definido), e avaliar a sua viabilidade celular para que essa possa ser uma fonte de probiótico. A levedura apresentou um acumulo de ferro e zinco durante os ciclos fermentativos, alcançando no final do sexto ciclo 8883 mg kg-1 de matéria seca e 7452 mg kg-1 de matéria seca respectivamente. A viabilidade celular das leveduras decresce durante todo o tempo de investigação, apresentando um valor de 82,53% aos 110 dias / The objective of this work was to accumulate the micro-nutrients iron and zinc in yeast Saccharomyces cerevisiae in broth with 300 mg L-1 of iron or zinc. The enriched live yeasts were studied to be added to a substrate (corn) sterilized by gamma radiation in order to be a potential source of pro-biotic. The yeast accumulated iron and zinc during the fermentative cycles, reaching 8,883 mg kg-1 (dry weight) and 7,452 mg kg-1 (dry weight), respectively, at the end of the sixth cycle. The cellular viability of the yeasts added to corn decreased during the period of investigation, presenting the value of 82,53% at 110 days
348

Enriquecimento ambiental para gatos domésticos (Felis silvestris catus L.): A importância dos odores / Environmental enrichment for domestic cats (Felis silvestris catus L.): The importance of odors

Gisele Cristina Guandolini 22 May 2009 (has links)
A transferência de odores entre os gatos e o meio ambiente ocorre por meio de contatos corporais, como também pela eliminação de excretas. Pelo enriquecimento ambiental é possível promover a exibição de comportamentos mais próximos dos naturais e extinguir comportamentos não desejáveis, contribuindo, assim, para a saúde física e psicológica dos animais. Este trabalho teve como objetivo promover estímulos no ambiente para que os gatos desempenhassem comportamentos característicos da espécie. Foram utilizados gatos domésticos (Felis silvestris catus L.), castrados (por volta do primeiro ano de vida) ou não, de ambos os sexos. Os animais foram mantidos todos juntos em um abrigo de gatos, cuja população era de aproximadamente 110 indivíduos, sendo 41 machos e 69 fêmeas. Cinco testes foram realizados durante dezesseis meses e foi registrado: quais os comportamentos são manifestados na área dos testes (grooming, urinar, defecar e verificações olfativas), quais indivíduos realizaram mais esses comportamentos (fêmeas, machos e machos castrados) e qual categoria animal apresentou maior número de contato. Foram utilizados o método animal focal e a amostragem do comportamento. Observou-se que existe diferença significativa nos contatos entre machos e fêmeas (Fr= 10, 362, p= 0, 006) e averiguou-se que essa diferença também ocorre quando os grupos são agregados (contatos F_M-M_M e contatos F_F-F_M). Fêmeas e machos castrados, quando comparados pelo teste Wilcoxon, apresentaram diferenças significativas no tempo dedicado ao comportamento de grooming(z= 2,95, p= 0,036). Os gatos são indivíduos bastante curiosos, o que facilita o desenvolvimento de um enriquecimento ambiental mais barato com o alcance de respostas comportamentais adequadas. / The transfer of odors between the cats and the environment occurs through physical contact, but also for disposal of excreta. For environmental enrichment can promote behaviors closer view of the natural and extinguish unwanted behaviors, thus contributing to the physical and psychological health of animals. This work aimed to promote the environment for stimuli that cats play behaviors characteristic of the species. We used domestic cats (Felis silvestris catus L.), castrated (around the first year of life) or not, of both sexes. The animals were kept together in a shelter for cats, whose population was approximately 110 individuals, 41 males and 69 females. Five tests were conducted over sixteen months and was recorded: which behaviors are manifested in the area of testing (grooming, urinate, defecate and verification olfactory), which made most people these behaviors (females, males and castrated males) and which category of animal presented more contact. We used the method of sampling and focal animal behavior. It was observed that there is significant difference in contacts between males and females (F = 10, 362, p = 0, 006) and checked that this difference also occurs when the groups are aggregated (F_M contacts and contacts F_F-M_M-F_M ). Females and castrated males, when compared by Wilcoxon test showed significant differences in time devoted to grooming behavior of (z = 2.95, p = 0.036). Cats are very curious people, which facilitates the development of an environmental enrichment cheaper with the range of appropriate behavioral responses.
349

Camundongos C57BL/6 alojados em ambiente enriquecido apresentam menor consumo de etanol após estresse. / C57BL/6 mice housed in enriched environment present lower ethanol consumption after stress.

Priscila Marianno 05 March 2015 (has links)
A retomada do consumo de etanol após abstinência é uma característica da dependência. O enriquecimento ambiental (EA) parece minimizar os efeitos de drogas de abuso, assim como a naltrexona (NTX). O estudo avaliou se EA, durante abstinência e associado ou não à NTX, alterou o consumo de etanol. Camundongos C57BL/6 foram expostos ao etanol 2h/dia. Após fase de aquisição, os animais foram separados em grupos. Os animais foram alojados em condições padrões e o outro em EA, 24h/dia ou 3h/dia. Após privação, os animais voltaram a ter acesso ao etanol semanalmente. Na última semana, tiveram acesso ao etanol por 24h e antes da reexposição foram submetidos ao estresse de contenção por 1h. Só neste caso, os grupos EA apresentaram uma redução no consumo de 24h. Ainda, outro experimento foi realizado associando o EA a baixas doses de NTX, mas não foram observadas alterações. Os resultados sugerem que o EA pode ajudar o animal a lidar melhor com o estresse, o que o protegeria de um comportamento de maior consumo de etanol. / The excessive ethanol consumption after abstinence is a feature of addiction. Environmental enrichment (EE) appears to minimize drug cravings, as well as naltrexone (NTX). The study evaluated whether EE during abstinence and with or without NTX, altered ethanol consumption. C57BL/6 mice were exposed to ethanol 2h/day. After an acquisition phase, mice were distributed into groups. The animals were housed in standard condition and the other in EE, 24h/day or 3h/day. After withdrawal, the animals returned to ethanol access weekly. On the last week, mice had access to ethanol for 24h and before re-exposure were subjected to restraint stress for 1h. EE groups decreased the ethanol consumption when mice had 24h free access to ethanol. Another experiment was performed with EE in association to low doses of NTX, but no differences in consumption were observed. The results suggests that EE may help the animal to cope better with stressful situations, resulting in blunted ethanol drinking.
350

Efeitos do enriquecimento ambiental sobre comportamentos induzidos pelo etanol em camundongos Swiss: envolvimento da circuitaria do estresse. / Effects of environmental manipulations on ethanol-related behaviors: involvement of the stress circuitry.

Mariana Beu Rae 23 April 2014 (has links)
O enriquecimento ambiental (EA) apresenta efeitos positivos sobre a dependência ao etanol e é possível que atue como um estressor leve, ajudando o animal a lidar melhor com situações adversas. Camundongos foram separados em três grupos: controle (CO), EA e estresse (ES). Foram estudados os efeitos do EA e ES no comportamento tipo ansiedade, memória episódica, preferência condicionada a lugar (CPP) com etanol, corticosterona e quantidade de receptor de oxitocina (OT). O EA diminuiu a latência de entrada no braço aberto, sugerindo efeito ansiolítico, ao contrário do ES. A memória não diferiu entre os grupos e o EA mostrou maior preferência condicionada ao etanol, comparado com CO. A corticosterona não mostrou diferença. A autorradiografia apontou diminuição da ligação de OT nos núcleos olfatórios e córtex frontal dos animais EA e aumento da ligação de OT na amígdala do ES em relação ao CO, sugerindo maior comportamento pró-social e maior ansiedade, respectivamente. Concluímos que o ambiente é capaz de afetar circuitos cerebrais envolvidos no estresse e dependência. / Environmental enrichment (EE) presents positive effects upon alcohol addiction and its possible that EE acts as a mild stressor, which would help animal cope better with future stressful situations. Mice were separated in three groups: control (CO), EE and stress (ST). We studied the effects of EE and ST on anxiety-like behavior, episodic memory, conditioned place preference (CPP) to ethanol, corticosterone and quantity of oxytocin receptor. EE decreased the latency to enter the open arm, suggesting an anxiolytic effect, unlike ST. Memory did not differ between groups and EE demonstrated a higher preference to ethanol compared to CO. Corticosterone levels didnt differ among groups. Autoradiography showed decreased binding of OT in the olfactory nuclei and frontal cortex of EE animals and enhanced binding of OT in the amygdala of ST animals compared to CO, suggesting higher pro-social behavior and higher anxiety-like behavior, respectively. We conclude that the environment is capable of affecting important brain circuitries involved in stress and drug addiction.

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