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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.
91

Vliv fluoranthenu na růstové a vývojové procesy okřehku menšího (Lemna minor L.)

Hrušková, Zuzana January 2014 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are considered persistent organic pollutants because of the long persistence in the environment. The presence of PAHs significantly responds aquatic plant Lemna minor L. reduction of its growth, and thus represents a bioindicator of organic load of the aquatic environment. The aim of this thesis was to evaluate the influence of fluoranthene on growth and developmental processes Lemna minor L. During the 21 days were observed at several concentrations of fluoranthene (0.1, 0.5, 1 and 5 mg / l) growth and viability of plants, morphological and anatomical changes and growth parameters. We also investigated the ability of plant production and changes in the content of phytohormones (cytokinins, ethylene, ABA). The results showed that fluoranthene had a significant effect on the appearance of plants and production of biomass, specific leaf area and leaf dry matter content. The production capabilities were no significant adverse effects. Due fluoranthene increased production of ethylene, and abscisic acid formation in plants duckweed. After 21 days of culture was observed in the plants treated with low concentrations of fluoranthene to synthesize iP, iPR and Z.
92

Růstová a metabolická odezva okřehku menšího (Lemna minor L.) na polycyklický aromatický uhlovodík

Hrušková, Zuzana January 2016 (has links)
Polycyclic aromatic hydrocarbons (PAHs) are ranked among the organic compounds with long-term permanence pollute the environment. The presence of PAHs react particularly aquatic plants. Duckweed (Lemna minor L.), water plant characterized in that it is exposed to foreign substances significant portion of his body, is a suitable model for the study of plant developmental and metabolic responses to the presence of polycyclic aromatic hydrocarbons. The aim of the thesis was to observe developmental and metabolic responses duckweed on the effect of polycyclic aromatic hydrocarbon fluoranthene. For 21 days were observed in four concentrations of fluoranthene, which accounted for commonly occurring (0.1 and 0.5 mg FLT / l) and slightly increased (1 and 5 mg FLT / L) concentrations of fluoranthene, metabolic and bioenergetic response. We were also observed growth and developmental changes and changes in the content of phytohormones. The study was focused on plant morphology. The results of this work, was evident that the presence of FLT has a significant impact on the appearance and production plants. It was also demonstrated a significant negative impact on the growth parameters. Fluoranthene demonstrated significant effects on the production of plant hormones.
93

Alkaloidy Vinca minor (Apocynaceae) a jejich biologická aktivita / Alkaloids of Vinca minor (Apocynaceae) and their biological activities

Klátilová, Anežka January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical botany Candidate: Anežka Klátilová Supervisor: doc. Ing. Lucie Cahlíková Ph. D. Title of diploma thesis: Alcaloids of Vinca minor (Apocynaceae) and their biological activities The aim of this diploma thesis was to process the assigned fraction isolated from the Vinca minor L. plant and to isolate at least one alkaloid to test its biological activity. Using preparative TLC, the alkaloid was sequentially isolated from the fraction, which was then subjected to a structural analysis. NMR and EI-MS methods were used herein. Thanks to these analyzes, the alkaloid was identified as venoterpine. Furthermore, the alkaloid was prepared to test for biological activity. Thus, the isolated alkaloid was identified as venoterpine and tested for biological activity. The observed inhibitory concentration (IC50) to HuAChE and HuBuChe was more than 500 μM, indicating that venoterpine does not rank as a significant inhibitor of cholinesterase. Likewise, the value of cytotoxic activity, when this activity was found to be greater than 10 μM to colorectal cancer cells as well as to healthy cells, is not significant. Key words: Vinca minor, Apocynaceae, alkaloids, biological activities
94

Avaliação de macrófitas lemnáceas no polimento de águas residuárias e seu uso na cultura do feijão / Evaluation of lemnaceal macrophites in water polishing residues and their use in bean culture

Lima, Rafael dos Santos 16 February 2018 (has links)
Submitted by RAFAEL DOS SANTOS LIMA (rafaelsantosnatureza@yahoo.com.br) on 2018-04-13T13:55:33Z No. of bitstreams: 1 Dissertação Rafael_9_Banca_ 5 3_FINALcom ficha.pdf: 1446594 bytes, checksum: 32e7e796d1433450c73715d155faef1b (MD5) / Approved for entry into archive by Maria Lucia Martins Frederico null (mlucia@fca.unesp.br) on 2018-04-16T11:46:32Z (GMT) No. of bitstreams: 1 lima_rs_me_botfca.pdf: 1426623 bytes, checksum: a5bfebbdd6fbee2ca22ec77b48e3cf2d (MD5) / Made available in DSpace on 2018-04-16T11:46:32Z (GMT). No. of bitstreams: 1 lima_rs_me_botfca.pdf: 1426623 bytes, checksum: a5bfebbdd6fbee2ca22ec77b48e3cf2d (MD5) Previous issue date: 2018-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A necessidade de preservação e uso racional da água é notória e pertinente. Esta reeducação também está associada ao uso de fontes alternativas, como a utilização de efluentes tratados (águas residuárias), para fins menos nobres, ou seja, aqueles nos quais não se requer água potável. É importante estudar o uso de novos insumos com potencial agrícola, onde a aplicação de águas de qualidade inferior à potável pode se tornar uma alternativa promissora para a obtenção de nutrientes e de água para as plantas de forma econômica e com menos impactos ambientais. Conhecendo a importância e necessidade do reuso da água e uso de efluentes na agricultura, este trabalho teve como objetivo geral, analisar o efeito das macrófitas lemnáceas no polimento de águas residuárias, bem como o uso dessa água na irrigação da cultura do feijão. O experimento foi realizado em casa de vegetação não climatizada no Departamento de Solos e Recursos Ambientais da FCA, UNESP, na cidade de Botucatu – SP. O cultivar utilizado foi o feijão IPR Andorinha e a macrófita aquática lamnácea utilizada foi a espécie Lemnas minor. Observou-se no presente experimento a remoção de 59% dos sólidos totais (ST) presentes na água residuária, podendo afirmar que esta redução está associada à hidrólise da matéria orgânica particulada, sedimentação e usos de macrófitas lamnáceas. No presente trabalho obtive-se uma redução de 74% na demanda química de oxigênio (DQO) em um tempo de detenção hidráulica (TDH) de 10 dias. A utilização de Lemnas minor no presente experimento foi significativa e eficaz no polimento da água residuária, pois a removeu 86% de fósforo (P). A irrigação com água residuária teve efeito significativo (p ≤ 0,05) no conteúdo de macro e micronutrientes no feijão, indicando que esta cultura tem capacidade de absorver e tolerar a utilização na irrigação de água residuária com e sem polimento. O índice de cor verde das folhas foi significativamente maior (p ≤ 0,05), aproximadamente 17,10%, no tratamento irrigado com água residuária com polimento em relação ao irrigado com água de abastecimento (potável). Enquanto que a água residuária sem polimento se assemelhou a ambas as formas de irrigação anteriores.
95

Tidal Tales of Minor Mergers: Star Formation in the Tidal Tails of Minor Mergers

January 2013 (has links)
abstract: This work examines star formation in the debris associated with collisions of dwarf and spiral galaxies. While the spectacular displays of major mergers are famous (e.g., NGC 4038/9, ``The Antennae''), equal mass galaxy mergers are relatively rare compared to minor mergers (mass ratio <0.3) Minor mergers are less energetic than major mergers, but more common in the observable universe and, thus, likely played a pivotal role in the formation of most large galaxies. Centers of mergers host vigorous star formation from high gas density and turbulence and are surveyed over cosmological distances. However, the tidal debris resulting from these mergers have not been well studied. Such regions have large reservoirs of gaseous material that can be used as fuel for subsequent star formation but also have lower gas density. Tracers of star formation at the local and global scale have been examined for three tidal tails in two minor merger systems. These tracers include young star cluster populations, H-alpha, and [CII] emission. The rate of apparent star formation derived from these tracers is compared to the gas available to estimate the star formation efficiency (SFE). The Western tail of NGC 2782 formed isolated star clusters while massive star cluster complexes are found in the UGC 10214 (``The Tadpole'') and Eastern tail of NGC 2782. Due to the lack of both observable CO and [CII] emission, the observed star formation in the Western tail of NGC 2782 may have a low carbon abundance and represent only the first round of local star formation. While the Western tail has a normal SFE, the Eastern tail in the same galaxy has an low observed SFE. In contrast, the Tadpole tidal tail has a high observed star formation rate and a corresponding high SFE. The low SFE observed in the Eastern tail of NGC 2782 may be due to its origin as a splash region where localized gas heating is important. However, the other tails may be tidally formed regions where gravitational compression likely dominates and enhances the local star formation. / Dissertation/Thesis / Ph.D. Astrophysics 2013
96

Menor: um problema para sociedade disciplinar

Karina de Oliveira Lima 29 June 2011 (has links)
A presente pesquisa investigou sobre e emergência do menor no período de 1889-1927. Utilizou-se como métodos de pesquisa a revisão bibliográfica sobre o tema e a pesquisa de fontes primárias. As ideias de Foucault sobre sociedade disciplinar, poder, saber governamentalidade, arqueologia e genealogia permitiram a análise dos autos encontrados sobre o menor evidenciando-se relações de poder e o processo de sujeição do menor pelo trabalho e pela educação. Constatamos, assim, como já apontado por autores estudiosos do tema que o trabalho e a educação constituíram-se elementos centrais nas políticas públicas dirigidas para o menor desde o período estudado até os dias de hoje / This research investigated and on the child emergency in the period 1889-1927. Was used as the research methods literature review on the subject and the research of primary sources. Foucault\'s ideas about society disciplinary power, governmentality know, archeology and genealogy allowed the analysis of the case found on the child evidencing power relations and the process of placing the child for the work and education. We have thus found, as pointed out by authors writing on this topic that work and education constituted the central elements in public policies directed to the child since the study period until the present day
97

Evaluation and ranking of minor-league hitters using a statistical model

Johnson, Gary Brent January 1900 (has links)
Master of Science / Department of Statistics / Thomas M. Loughin / Traditionally, major-league scouts have evaluated young “position players,” those who are not pitchers, using the “Five Tools”: hitting for average, hitting for power, running, throwing, and fielding. However, “sabermetricians,” those who study the science of baseball, e.g. Bill James, have been trying to evaluate position players using quantifiable measures of performance. In this study, a factor analysis was used to determine underlying characteristics of minor-league hitters. The underlying factors were determined to be slugging ability, lead-off hitting ability, “patience” at the plate, and pure-hitting ability. Additionally, an ordinal response was created from the number of at-bats and on-base plus slugging percentage in the majors during the 2002-05 seasons. The underlying characteristics along with other variables such as a player’s age, position, and level in the minors are used in a cumulative logit logistic regression model to predict a player’s probability of notable success in the majors. The model is built upon data from the 2002 minor-league season and data from the 2002, 2003, 2004, and 2005 major-league seasons.
98

The Putative Cerean Exosphere

Schorghofer, Norbert, Byrne, Shane, Landis, Margaret E., Mazarico, Erwan, Prettyman, Thomas H., Schmidt, Britney E., Villarreal, Michaela N., Castillo-Rogez, Julie, Raymond, Carol A., Russell, Christopher T. 20 November 2017 (has links)
The ice-rich crust of dwarf planet 1 Ceres is the source of a tenuous water exosphere, and the behavior of this putative exosphere is investigated with model calculations. Outgassing water molecules seasonally condense around the winter pole in an optically thin layer. This seasonal cap reaches an estimated mass of at least 2 x 10(3) kg, and the aphelion summer pole may even retain water throughout summer. If this reservoir is suddenly released by a solar energetic particle event, it would form a denser transient water exosphere. Our model calculations also explore species other than H2O. Light exospheric species escape rapidly from Ceres due to its low gravity, and hence their exospheres dissipate soon after their respective source has faded. For example, the theoretical turn-over time in a water exosphere is only 7 hr. A significant fraction of CO2 and SO2 molecules can get trapped and stored in perennially shadowed regions at the current spin axis orientation, but not at the higher spin axis tilt, leaving H2O as the only common volatile expected to accumulate in polar cold traps over long timescales. The D/H fractionation during migration to the cold traps is only about 10%.
99

Accumulation and toxicity of cadmium, lead and thallium in duckweed (Lemna minor L.)

Mohammed, Dana January 2017 (has links)
Accumulation and toxicity of cadmium, lead and thallium in duckweed (Lemna minor L.) The toxicity and accumulation of lead, cadmium and thallium in the aquatic plant Lemna minor was investigated, using a modification of the Organisation for Economic Co-operation and Development (OECD) standard growth inhibition test. Plants were cultured in modified Swedish Institute Standard (SIS) at pH 6.5±0.5 under 85 µmol m-2 S-1 at 25°C and exposed to a wide range of lead, cadmium, and thallium concentrations from environmentally realistic to very high concentrations (0.001, 0.01,0.1, 1, 10, 100, 1000 and 10 000 µmol L-1) for seven days. Various physico-biochemical endpoints were measured after seven days of exposure. The concentrations of dissolved lead, cadmium, and thallium remaining in the residual solutions, and accumulation of lead, cadmium and thallium in fronds and roots were assessed using Inductively Couple Plasma – Mass Spectroscopy (ICP-MS). Over the exposure duration, lead, cadmium, and thallium concentrations in solution decreased rapidly and chlorosis was observed in fronds exposed to the three highest lead, cadmium, and thallium concentrations. After seven days of exposure, there were significant decreases in the relative growth rate (RGR), relative frond area (RFA), pigment content (chlorophyll a, b and total carotenoid) and activity of photosystem II (Fv/Fm) at concentrations of 0.1, 1, 10, 100, 1000 and 10 000 µmol L-1Pb, 10, 100, 1000 and 10 000 µmol L-1cd, 0.01,0.1, 1, 10, 100, 1000 and 10 000 µmol L-1TI. However, our results suggested that root elongation based on relative growth rate of L. minor will be an optimal and relevant endpoint in compare to other endpoints. As expected, results demonstrated that root elongation was concluded that root length was most predictive of a dose response model compared to the rest of growth endpoints and physiological and biochemical endpoints when assessing toxicity of lead, cadmium and thallium using L. minor. Toxicity testing for the floating macrophytes should include root elongation measurement which alone will be sufficient to meet sensitivity and variability requirements for toxicity testing. Cellular concentrations of lead, cadmium, and thallium were higher in roots than fronds, whereas more lead, cadmium, and thallium was adsorbed to the extracellular matrix of fronds than roots. The bio - concentration factor (BCF; i.e. lead concentration in plant tissue at day seven relative to residual lead concentration in the growth medium at day seven) indicates that L. minor is a good accumulator of lead, cadmium, and thallium particularly at lower concentration, but the physiological data shows that these metals toxic at concentrations that can be encountered in wastewater treatment facilities. The translocation factor (TF) value was found to be less than 1. Though, lead, cadmium and Thallium was mostly stored in roots, only minor amounts of lead, cadmium and thallium were trans located to fronds.
100

Tonal multiplicity in Schoenberg’s first string quartet, op.7

Cavanagh, Lynn Marie 11 1900 (has links)
This study describes the integration of harmonic idiom and tonal design in Schoenberg's First Quartet, op. 7. Two general questions are answered: whether the composition should be judged by common-practice-period norms, and whether a coherent tonal structure is truly discernible. Chapter 1 first surveys the existing literature. It then describes a prime motivator of foreground chromaticism in the quartet—the chromatic surrounding of tonic and dominant pitches—and discusses two features of large-scale pitch organization applicable to Schoenberg's first-period music that contravene common-practice-period norms: tonal structure consisting of a pattern of keys, and systematic use of dual or even multiple tonics in place of monotonality. Examples illustrate three types of graphic representation of tonal duality to be used in the study. The next four chapters describe tonal process within and across the four "movements" of the quartet (Schoenberg's Parts I through IV). Chapter 2, which studies Part I, reveals systematic avoidance of V-I function in the opening key, D, tonal rivalries between D and each of its two semitone-related keys, and the beginning of a large-scale chromatic surrounding of the key of D. Chapter 3, on Part II of the quartet, demonstrates continuation of the rivalry between tonics D and Dt> by their use as competing secondary tonics within the Scherzo, and the harmonic progression VII-I replacing V-I at a crucial structural point. Chapter 4, on Part III of the quartet, describes tonal duality as it occurs in the Adagio, the furthering of the tonal plot in a section that engages in a "plagal" system of tonality, and the beginning of a large chromatic surrounding of A. Chapter 5 shows that Part IV eschews a simple relationship between the A-major tonic of the Rondo and the D-major tonic of the Coda by allowing the infiltration of elements of the Db-major collection. Chapter 6 summarizes the evidence contradicting a monotonal understanding of the composition and reviews evidence that the demonstrated multi-tonal coherence is part of the musical reality of the work. / Arts, Faculty of / Music, School of / Graduate

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