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Estudo fitoqu?mico de Byrsonima coccolobifolia Kunth (Malpighiaceae) e de atividade biol?gica de esp?cies do g?nero ByrsonimaPereira, Vin?cius Viana January 2011 (has links)
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Previous issue date: 2013-02-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Esp?cies do g?nero Byrsonima s?o conhecidas popularmente como ?muricis? e h? relatos na literatura de muitos usos medicinais dessas plantas, alguns deles j? comprovados, como atividade anti-inflamat?ria, antimicrobiana e antioxidante. Este trabalho objetivou analisar fitoquimicamente a esp?cie Byrsonima coccolobifolia Kunth e fazer um estudo de atividade biol?gica nos extratos de B. coccolobifolia, B. verbascifolia e B. intermedia, investigando a atividade antioxidante, a a??o inibit?ria da acetilcolinesterase e atividade antimicrobiana nessas esp?cies. As partes a?reas das plantas foram coletadas no Vale do Jequitinhonha-MG e secas a temperatura ambiente. Folhas e galhos foram separados, pulverizados e submetidos ? extra??o exaustiva com solventes de polaridade crescente (hexano, acetato de etila e metanol), que foram removidos por evaporador rotat?rio. Os extratos em hexano e em acetato de etila de B. coccolobifolia foram submetidos a m?todos cromatogr?ficos cl?ssicos e, atrav?s de t?cnicas espectrosc?picas (IV e RMN de 1H e 13C), foi poss?vel elucidar nos extratos das folhas as seguintes subst?ncias: friedelina, ?-sitosterol, mistura de ?-amirina e ?-amirina e derivados do ?cido olean?lico e urs?lico. Na identifica??o dos compostos presentes no extrato metan?lico de folhas e galhos de B. coccolobifolia, utilizou-se a t?cnica de espectrometria de massas por electrospray (ESI-MS), por inser??o direta dos extratos dissolvidos em metanol. Identificaram-se tr?s classes de metab?litos no extrato metan?lico: ?cidos fen?licos e derivados (galato de metila, ?cido qu?nico, ?cidos mono-, di-, tri- e tetragaloilqu?nico), proantocianidinas (d?mero e tr?mero epicatequina) e flavon?ides (quercetina e derivados glicosilados). As esp?cies B. coccolobifolia e B. intermedia apresentaram os melhores resultados para conte?do fen?lico e para atividade antioxidante de captura de radical e de poder redutor. Isso mostrou o potencial dos extratos polares dessas plantas como recurso para a busca de subst?ncias ?teis na preven??o ou no tratamento de doen?as associadas a radicais livres. No que diz respeito ? atividade inibit?ria da acetilcolinesterase (AChE), tamb?m investigada nas tr?s esp?cies de Byrsonima, o extrato hex?nico dessas plantas apresentou maior quantidade de compostos ativos frente a enzima AChE. E somente a esp?cie B. coccolobifolia apresentou atividade contra os microrganismos testados (Staphylococcus aureus, Bacillus cereus, Escherichia coli e Candida albicans). Sendo assim, o presente trabalho mostrou a import?ncia de continuar estudando a flora do cerrado brasileiro e as esp?cies do g?nero Byrsonima, sejam seus aspectos qu?micos ou medicinais. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2011. / ABSTRACT
Byrsonima species are popularly known as "murici" and there are reports in previous work of many medicinal uses of these plants, some of them already confirmed as anti-inflammatory, antimicrobial and antioxidant activities. The aim of this study was to analyze phytochemically Byrsonima coccolobifolia Kunth and to make a study of biological activity in extracts of B. coccolobifolia, B. verbascifolia and B. intermedia, investigating the antioxidant activity, acetylcholinesterase inhibitory action and antimicrobial activity in these species. The aerial parts of plants were collected in Jequitinhonha Valley, Minas Gerais, Brazil, and dried at room temperature. Leaves and branches were separated, powdered and subjected to exhaustive extraction with solvents of increasing polarity (hexane, ethyl acetate and methanol), that were removed by rotary evaporator. The extracts in hexane and ethyl acetate of B. coccolobifolia were submitted at classical chromatographic methods and, by spectroscopic methods (IR and 1H and 13C NMR), it was possible to elucidate the following substances in leaves extracts: friedelin, ?-sitosterol, a mixture of ?-amyrin and ?-amyrin and oleanolic and ursolic acid derivatives. In the identification of compounds in methanol extracts of leaves and branches of B. coccolobifolia was used mass spectrometry with electrospray (ESI-MS) by direct infusion of the extracts dissolved in methanol. Three classes of metabolites were identified in methanol extracts: phenolic acids and derivatives (methyl gallate, quinic acid, mono-, di-, tri- and tetragalloylquinic acids), proanthocyanidins (epicatechin dimer and trimer) and flavonoids (quercetin and glycosides derivatives). The species B. coccolobifolia and B. intermedia showed better results for phenolic content and antioxidant activity of radical scavenging and reducing power. This showed the potential of polar extracts of these plants as a resource to search for substances useful in preventing or treating diseases associated with free radicals. Concerning the inhibitory activity of acetylcholinesterase (AChE), also investigated in three Byrsonima species, hexane extract of these plants had higher amounts of active compounds against AChE. And only B. coccolobifolia revealed activity against the microorganisms tested (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Candida albicans). Thus, this investigation supported the importance of further studying the flora of Brazilian cerrado and the species of the genus Byrsonima, in their chemical or medicinal aspects.
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Da prote??o ? precariza??o um estudo do fen?meno jur?dico trabalhista no contexto das transforma??es do capitalismoMenezes, Patr?cia Moreira de 08 October 2012 (has links)
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Previous issue date: 2012-10-08 / This research aims to investigate the effectiveness of the legal labor phenomenon
in contemporary capitalism as rectifier element of the contradictions between capital
and labor. From the analysis of legislative developments - state and business - and
court decisions related to the category of freight transport is expected to determine
the protectionist stiffness proclaimed by the institutional structure of labor in Brazil,
considered by the hegemonic discourse as political-economic factor that prevents
growth. It is intended to unravel the relationships between political and civil society,
studying the internal contradictions and ideological influence among these spaces,
with theoretical support in Marx and Gramsci. The function of this research is to test
the premise that the protectionist discourse is a rational action of capitalism and the
organic intellectuals of political society in order to achieve hegemony and hide the
real contradictions between capital and labor, in addition to also assist in the
discussion on deregulation and easing in Brazil. The analysis points to the
confirmation of our premise, since the evolution of the legal phenomenon in the
transport sector was charging toward the neoliberal project / Esta pesquisa se prop?e investigar a efetividade do fen?meno jur?dico trabalhista
no capitalismo atual como elemento retificador das contradi??es entre capital e
trabalho. A partir da an?lise da evolu??o legislativa - estatal e negocial - e de
decis?es judiciais relacionadas ? categoria de transportes de carga, espera-se
averiguar a proclamada rigidez protecionista da estrutura institucional trabalhista no
Brasil, considerada pelo discurso hegem?nico pol?tico-econ?mico como fator que
impede o crescimento. Pretende-se desvendar as rela??es entre sociedade pol?tica
e sociedade civil, estudando as contradi??es internas e a influ?ncia ideol?gica entre
estes espa?os, com aporte te?rico em Marx e Gramsci. A fun??o da investiga??o ?
testar a premissa que o discurso protecionista ? uma a??o racional do capitalismo e
dos intelectuais org?nicos da sociedade pol?tica, a fim de alcan?ar hegemonia e
ocultar as contradi??es reais entre capital e trabalho; al?m de tamb?m auxiliar na
discuss?o sobre a desregulamenta??o e a flexibiliza??o no Brasil. A an?lise aponta
para a confirma??o da nossa premissa, posto que a evolu??o do fen?meno jur?dico
no setor de transporte de carga foi na dire??o do projeto neoliberal
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Degrada??o foto-fenton de carbono org?nico total em efluentes da ind?stria de beneficiamento de castanha de cajuSouza, K?tia Regina 16 December 2005 (has links)
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Previous issue date: 2005-12-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / At the cashew nut processing industry it is often the generation of wastewaters containing high content of toxic organic compounds. The presence of these compounds is due mainly to the so called liquid of the cashew nut (CNSL). CNSL, as it is commercially known in Brazil, is the liquid of the cashew nut. It looks like an oil with dark brown color, viscous and presents a high toxicity index due to the chemical composition, i.e. phenol compounds, such as anacardic acid, cardol, 2-methyl cardol and monophenol (cardanol). These compounds are bio resistant to the conventional treatments. Furthermore, the corresponding wastewaters present high content of TOC (total organic carbon). Therefore due to the high degree of toxicity it is very important to study and develop treatments of these wastewaters before discharge to the environmental. This research aims to decompose these compounds using advanced oxidative processes (AOP) based on the photo-Fenton system. The advantage of this system is the fast and non-selective oxidation promoted by the hydroxyl radicals (●OH), that is under determined conditions can totally convert the organic pollutants to CO2 and H2O.
In order to evaluate the decomposition of the organic charge system samples of the real wastewater od a processing cashew nut industry were taken. This industry was located at the country of the state of Rio Grande do Norte. The experiments were carried out with a photochemical annular reactor equipped with UV (ultra violet) lamp. Based on preliminary experiments, a Doehlert experimental design was defined to optimize the concentrations of H2O2 and Fe(II) with a total of 13 runs. The experimental conditions were set to pH equal to 3 and temperature of 30?C. The power of the lamps applied was 80W, 125W and 250W. To evaluate the decomposition rate measures of the TOC were accomplished during 4 hours of experiment. According to the results, the organic removal obtained in terms of TOC was 80% minimum and 95% maximum. Furthermore, it was gotten a minimum time of 49 minutes for the removal of 30% of the initial TOC. Based on the obtained experimental results, the photo-Fenton system presents a very satisfactory performance as a complementary treatment of the wastewater studied / Na ind?stria de beneficiamento de castanha de caju ? bastante freq?ente a produ??o de efluentes com altas concentra??es de compostos org?nicos de origem t?xica. A presen?a desses compostos se deve ao LCC contido nas ?guas residu?rias. O LCC ? conhecido comercialmente como l?quido da castanha de caju e tem a apar?ncia de um ?leo de cor marrom escura e viscosa. A toxicidade desse efluente, deve-se ? sua composi??o qu?mica formada por compostos fen?licos, tais como, ?cido anac?rdico, derivados do resorcinol (cardol e 2-metil cardol) e um monofenol (cardanol), entre outros, resistentes aos tratamentos convencionais. Estes efluentes apresentam, invariavelmente, elevados valores de carbono org?nico total (COT). Devido ao grau de toxicidade, ? de grande import?ncia o tratamento desses efluentes antes da sua descarga no meio ambiente. O objetivo desse trabalho foi analisar a ocorr?ncia da degrada??o de COT utilizando o processo oxidativo avan?ado (POA) baseado no sistema foto-Fenton. A vantagem deste sistema ? a oxida??o r?pida e n?o seletiva promovida pelo radical hidroxila (●OH), que sob certas condi??es podem promover a convers?o total dos poluentes org?nicos a CO2 e H2O. Para a avalia??o da degrada??o foi utilizado amostras do efluente aquoso bruto (n?o tratado) de uma ind?stria de beneficiamento de castanha de caju localizada no interior do RN. Os experimentos foram realizados em um reator fotoqu?mico anular de fluxo ascendente, cuja concentra??o de Fe(II) e H2O2 foi baseado em testes preliminares e atrav?s do planejamento experimental Doehlert. As condi??es iniciais dos experimentos foram: ajuste do pH inicial para 3,0, temperatura do sistema foi mantida constante a 30?C e as pot?ncias das l?mpadas usadas foram de 80W, 125W e 250W. Todos os experimentos foram realizados em 4h. Os crit?rios para se avaliar a efici?ncia do sistema foram: a ocorr?ncia da degrada??o atrav?s do valor de COT, colora??o final do efluente ap?s tratamento. De acordo com esses crit?rios foram obtidos os seguintes resultados: a porcentagem de remo??o de COT m?nima 80% e m?xima 95%, tempo m?nimo de irradia??o necess?rio para remo??o 30% do COT inicial foi 49 minutos. Pelos resultados experimentais obtidos, foi conferido um bom desempenho do sistema foto-Fenton como tratamento complementar na remo??o de COT presente nas ?guas residu?rias da ind?stria de beneficiamento de castanha de caju
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Modelo de Ashkin-Teller anisotr?pico: uma abordagem por grupo de renormaliza??oBezerra, Claudionor Gomes 24 May 1994 (has links)
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Previous issue date: 1994-05-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Estudamos as propriedades cr?ticas (diagrama de fases e classes de universalidade) do modelo de Ashkin-Teller anisotr?pico ferromagn?tico, cujo hamiltoniano ? dado por:
H = -∑_(<ij>)▒〖{J1TiTj+J2σiσj+J4σiσjTiTj}〗
com: J1 + J2 ≥ 0, J1 + J4 ≥ 0 , J2 + J4 ≥ 0, ( σ, r = ? 1 ).
Utilizamos o m?todo do Grupo de Renormaliza??o no espa?o real, aplicado a uma rede hier?rquica que serve como aproxima??o para a rede quadrada.
Observamos a exist?ncia de 5 fases :
(i) Paramagn?tica ( P : < σ > =< Ƭ > =< σƬ >= 0) ;
(ii) Intermedi?ria ( I : < σ > =< Ƭ >= 0, < σƬ > ≠ 0) ;
(iii) Ferromagn?tica ( F : < σ > ≠ 0, < Ƭ > ≠ 0, < σƬ > ≠ 0) ;
(iv) Ferro σ ( Fσ : < σ > ≠ 0, < Ƭ >=< σƬ >= 0 ) ;
(v) Ferro σ ( FƬ : < Ƭ > ≠ 0, < σ >=< σƬ >= 0 ).
As fronteiras cr?ticas obtidas reproduzem todos os valores exatos conhecidos (em pontos especiais) para a rede quadrada
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Desastres naturais: uma an?lise dos decretos de estiagem e seca no Estado do Rio Grande do NorteRibeiro, Marcos Samuel Matias 30 May 2016 (has links)
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Previous issue date: 2016-05-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Os Desastres Naturais (DN) s?o estabelecidos pela ocorr?ncia de fen?menos naturais em ?reas ou regi?es habitadas, e caracterizados pelo fato de seu impacto causar danos ? popula??o afetada. Caso n?o apresente danos ? sociedade ou aconte?a em ?reas n?o ocupadas, o fen?meno ? considerado apenas um evento natural. As ocorr?ncias de Desastres Naturais originam grandes problemas e preju?zos para as sociedades afetadas, al?m de ocasionar grandes perdas humanas. O objetivo do trabalho ? realizar uma an?lise das ocorr?ncias dos DN nas dezenove microrregi?es do estado do Rio Grande do Norte, no per?odo de1991 a2012, tra?ando um paralelo com os registros ao longo do tempo dos limiares de precipita??o. Utilizou-se de t?cnicas estat?sticas, como an?lise espacial para a constru??o de mapas tem?ticos de forma a identificar ?reas com maior risco, e o teste de qui-quadrado para verificar associa??es entre as vari?veis. O ?ndice de Precipita??o Padronizado (SPI) foi considerado, objetivando evidenciar as condi??es meteorol?gicas das ?reas analisadas no momento da publica??o dos Decretos de Estado de Emerg?ncia ou Calamidade P?blica. Os resultados demonstraram um aumento expressivo de 98,7% nos registros das ocorr?ncias para o Estado, uma vez que nos 11 (onze) primeiros anos foram registrados 535 ocorr?ncias e nos 11 anos subsequentes foram registrados 1.063, com um total de 2.447.683 pessoas afetadas por DN. Para o Estado, os fen?menos que apresentaram maior frequ?ncia foram: as estiagem/seca (81,1%), as enxurradas e as inunda??es (18,9%), provenientes das rela??es de fatores com caracter?sticas entre o natural e social. Os dados apresentaram rela??es estatisticamente significativas entre as ocorr?ncias para os dois per?odos em an?lise, bem como sua rela??o com a precipita??o m?dia acumulada anual. A compreens?o deste comportamento ao longo do tempo levar? as autoridades competentes, a identificar as condi??es que se encontra a sociedade, possibilitando no direcionamento de a??es e pol?ticas p?blicas eficazes na gest?o para a mitiga??o do risco a desastres naturais. / The Natural Disasters (DN) are established by the occurrence of natural phenomena in areas or regions inhabited, and characterized by the fact that its impact damage to the affected population. If undamaged to the company or happen in areas not occupied, the phenomenon is considered just a natural event. The Natural Disaster occurrences originate great problems and damage to the affected societies besides causing great human losses. The objective is to analyze the occurrence of DN in nineteen micro-regions of Rio Grande do Norte state, in the period 1991-2012, drawing a parallel with the records over time of rainfall thresholds. We used statistical techniques, as a spatial analysis to build thematic maps to identify areas with increased risk, and the chi-square test to verify associations between variables. The Standardized Precipitation Index (SPI) was considered, aiming to highlight the weather conditions of the areas analyzed at the time of publication of Decree of the State of Emergency and Public Calamity. The results showed a significant increase of 98,7% in the records of events for the state, once in eleven (11) years were first registered 535 occurrences and the subsequent 11 years were recorded 1.063, a total of 2.447,683 people affected by DN. For the state, the phenomena that most frequently presented were: the drought / dry (81,1%), flash floods and floods (18,9%), from the relations of factors with characteristics between the natural and social. The data show statistically significant relationships between the occurrences for the two periods, and its relationship with the annual cumulative average rainfall. Understanding this behavior over time will lead the competent authorities, to identify the conditions that is society, enabling the direct actions and effective public policies in the management to mitigate the risk of natural disasters.
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Einfluss von Wiedervernässungsmaßnahmen auf den Stoffhaushalt degradierter NiedermooreVelty, Silke 08 April 2008 (has links)
Zur Einschätzung der Auswirkungen einer Wiedervernässungsmaßnahme auf den Stoffhaushalt eines degradierten Niedermoores wurde ein ehemals entwässertes und seit 1996 wieder vernässtes ca. 10 Hektar großes Areal im Randow-Welse-Bruch im nordöstlichen Brandenburg über mehrere Jahre untersucht. Stoffkreisläufe wurden vor allem in Abhängigkeit der sich durch die Wiedervernässung ändernden Redoxbedingungen modifiziert. Obwohl Phosphor, ein die Eutrophierung auslösendes Element, selbst direkt nicht durch einen Wechsel von aeroben zu anaeroben Bedingungen durch die Wiedervernässung beeinflusst wird, änderte sich dessen Mobilität auf Grund der Rücklösung seines Sorptionspartners. Infolge der anhaltend reduzierenden Bedingungen fand nach mehrjähriger Wiedervernässung der Prozess der Rücklösung amorpher Eisen(hydr)oxide statt, wobei der ehemals an diese Verbindungen fixierte Phosphor freigesetzt wurde. Bei Niedermooren, die infolge hoher Gehalte an Eisen(hydr)oxiden ein erhöhtes Phosphor-Freisetzungspotenzial besitzen, sollte eine Wiedervernässung mit gereinigtem kommunalen Abwasser nicht in Erwägung gezogen werden. Die Erfassung der gasförmigen Emissionen ermöglichte eine Berücksichtigung innerhalb der Stoffbilanzierung und eine Bewertung der Wiedervernässungsmaßnahme hinsichtlich ihrer Klimarelevanz. Auf Grund des anaeroben Milieus durch die Wiedervernässung wurde neben Lachgas auch molekularer Stickstoff als gasförmige Stickstoffverbindung gebildet. Gegenüber der entwässerten Lysimetervariante zeigte sich ein positiver Beitrag zur Reduzierung des Treibhauseffektes durch die Wiedervernässung. Jedoch ist die Qualität des Zusatzwassers, das zur Wiedervernässung der Torfprofile des Niedermoores Havelländisches Luch eingesetzt wurde, entscheidend. In eutrophen Niedermoorökosystemen sind nährstoffreiche Wasserzuflüsse aus kommunalen Abwasserbehandlungsanlagen als Wiedervernässungsmaßnahme geeignet, so dass gereinigtes Abwasser den Landschaftswasserhaushalt stützen könnte. / A formerly drained, and since 1996 rewetted, 10 ha fen site within the Randow-Welse-Bruch fen area in northeastern Brandenurg (Germany) has been investigated for several years to evaluate the impacts of rewetting on nutrient dynamics of the degraded fen. Modifications of nutrient cycles were attributed to changes in redox conditions after rewetting. Although phosphorus which causes eutrophication is not directly influenced by a change from aerobic to anaerobic conditions following rewetting its availability increased due to the dissolution of reactive iron (hydr)oxides where phosphorus was fixed before.With prolonged water-logging phosphorus was released from Fe(III) (hydr)oxides. A lysimeter study was carried out to promote the reuse of purified municipal wastewater as an alternative solution for water supply required during rewetting of fens. Fen soil lysimeters were irrigated with wastewater of the secondary treatment of a municipal wastewater treatment plant over the growing seasons. The objective of this study was to assess how restoration of a degraded fen by means of wastewater usage affects input/output nutrient mass balances. Furthermore, we assessed the effect on trace gas emissions and discussed potential changes in the greenhouse potential. No adverse impact of wastewater utilisation for rewetting the fen soil lysimeters on soil and water quality was found over the period of study with regard to the investigated nutrients and heavy metals. Gaseous fluxes during alternative rewetting were estimated for a consideration within nutrient balances and to evaluate the global warming and cooling, respectively. Besides nitrous oxide dinitrogen was formed and released under anaerobic conditions following rewetting. A potential increase of the nitrate concentration in wastewater would be harmless because a high denitrification of the fen soil would cause a major share of dinitrogen emissions of the total gaseous nitrogen loss.
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Zwischen Niedermoor und BodenChmieleski, Jana 25 April 2007 (has links)
Böden aus Mudde entstehen in ehemaligen Seen, meist unter Luftzutritt infolge von künstlicher Entwässerung. Entwässerung und Nutzung führen zu einer sekundären Pedogenese, einhergehend mit der Veränderung der chemischen und physikalischen Bodeneigenschaften. Die nachhaltige Nutzung dieser meist jungen Böden ist von besonderer Bedeutung, da es sich überwiegend um Niedermoorflächen mit großer Bedeutung der Filter- und Speicher- sowie der Lebensraumfunktion handelt. Dabei ist, um negative Konsequenzen ihrer Entwicklung zu verhindern, folgende Wirkungskette zu untersuchen: Entstehung des subhydrischen Sedimentes -> Entwässerung -> landwirtschaftliche Nutzung und Bodenentwicklung -> Degradation. In Nordeuropa sind Böden aus Mudde vor allem in Norddeutschland und Polen sowie Finnland und Schweden zu finden. Es wurden 60 Bodenprofile auf 13 Untersuchungsflächen in Deutschland und Polen detailliert beschrieben und untersucht. Dabei erfolgte für jeden Horizont die Entnahme von ungestörten Proben mittels Stechzylindern für die Analyse der bodenphysikalischen Parameter (pF-Kurven, Trockenrohdichte) und von gestörten Beutelproben für die chemische Analytik (Glühverlust, Kalkgehalt, Elementgehalte mittels RFA und ICP). Bisher noch nicht beschriebene Horizonte wurden vorzugsweise anhand des Bodengefüges identifiziert. Mudden unterscheiden sich in ihrer mineralischen Zusammensetzung erheblich von allen anderen Ablagerungen. Der Anteil an organischer Substanz und Kalziumkarbonat beträgt zwischen 5 und 95 %. Wegen ihres hohen Anteils an kleinen Partikeln weisen sie ein sehr großes Porenvolumen bis zu 90 % auf, wobei die Mittel- und Feinporen mehr als 50 % ausmachen. Das Porenvolumen steigt mit dem Anteil an organischer Bodensubstanz. Als Folge der Bodenentwicklung verringert sich das Porenvolumen bei gleichzeitiger Zunahme des Anteils der Feinporen auf Kosten der Mittelporen. / The formation of gyttja soils takes place in former lakes, predominantly under aeration. This phenomenon of now terrestrial, but formerly subhydric soils (so called gyttja soils) is mainly due to artificial drainage. Their cultivation led to a secondary pedogenesis, which had an effect on their chemical and physical properties. Thus, the sustainable use of this special type of very young land (subhydric soils) is of special importance. Hence, special emphasis has to be directed towards evaluating sequential changes: formation of sediment under water -> drainage/drying -> agricultural use/pedogenesis -> degradation/devastation in order to prevent negative consequences for the environment. In Northern Europe, gyttja deposits can be found in Northern Germany, Finland, Sweden, and mainly in Poland. 13 sites in Germany and Poland with gyttja soils have been investigated. A total of 60 profiles are described in detail. For each horizon, undisturbed samples for physical (tension curves for pF 1.5, 1.8, 2.0, 2.5 and 4.2, dry bulk density) and disturbed samples for chemical analysis have been taken (loss on ignition, CaCO3 content, X-ray fluorescence spectroscopy). Previously not described horizons could be visually distinguished mainly by their structure. Subhydric soils have a very specific composition, which differs greatly from other soils. The amount of organic matter and CaCO3 ranges from 5 to 95 %. Almost all sediments contain a high amount of very small particles and, as a consequence, a high pore space volume of up to 90 %. The amount of the medium and micro-pores is more than 50 %. The porosity increases with the content of organic matter. As a result of pedogenesis, the porosity decreases while the volume of micro-pores increases and the volume of medium pores decreases.
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Gelöster organischer Kohlenstoff an Niedermoorstandorten NordostdeutschlandsSchwalm, Mayte 11 March 2015 (has links)
Austräge von gelöstem organischem Kohlenstoff (DOC) aus Mooren sind aus Gründen des Klima- und Trinkwasserschutzes unerwünscht. Einflüsse von Landnutzung auf die Höhe der DOC-Konzentrationen werden teilweise inkonsistent beschrieben und überdies sind wenige Angaben zu den stark anthropogen überprägten Niedermooren Nordostdeutschlands verfügbar. Daher sind in der vorliegenden Arbeit Zusammenhänge von Management und Standorteigenschaften zu DOC-Konzentrationen auf Lysimeter- und Freilandebene untersucht worden. Es zeigte sich, dass die DOC-Gehalte des wiedervernässten Niedermoores deutlich und die DOC-Austräge tendenziell geringer waren als am landwirtschaftlich genutzten Standort, und dass die DOC-Konzentrationen im Grabenwasser seit der Wiedervernässung gesunken sind. Die unmittelbar durch Landnutzung beeinflussten Parameter Wasserstand und Vegetation waren in Lysimeterversuchen von untergeordneter Bedeutung. Niedermoore scheinen bedingt durch ihre individuelle Genese ein spezifisches DOC-Potential bzw. einen „Fingerabdruck“ zu haben, weshalb bei Wiedervernässung zwar sinkende, aber nicht unbedingt geringe, naturnahen DOC-Konzentrationen erreicht werden können. / Losses of dissolved organic carbon are of environmental concern, as DOC is a potential source of gaseous carbon emissions and harms drinking water quality. Lack of knowledge particularly exists for lowland fens. Therefore, the influence of land management and site characteristics on DOC was studied at a catchment and a lysimeter scale. A rewetted fen was investigated showing considerabely lower ditch DOC concentrations and slightly lower DOC losses as compared to an agriculturally used fen. The influence of water levels and vegetation was relatively small in lysimeter trials, while each fen soil seems to have a specific potential for DOC release due to its susbtrate quality and genesis.
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Um estudo sobre as refer?ncias de Winnicott aos fen?menos psicossom?ticosFaria, Cl?udia Mezzarano 24 February 2012 (has links)
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Previous issue date: 2012-02-24 / The aim of this study was to clarify Winnicott s understandings of the psychosomatic problems, especially those related to the genesis, dynamics and potential treatment, thus contributing to the development of his psychosomatic theory. Several cases and clinical vignettes with psychosomatic symptoms and references, scattered in his work, were gathered, organized and classified. Data analysis was based on these references in relation to the theory. Beginning with the notions of integration psyche-soma and personalization, Winnicott considers the real psychosomatic disorder related to primary (early) development processes. He assumes the commonly called psychosomatic disorder phenomenon is only the body-psyche connection (linkage). Furthermore, he assumes that in several cases, the physical manifestations of psycho-emotional difficulties are natural phenomenon of human life and part of the maturation process. The classification of cases and clinical vignettes was proposed as follows: False psychosomatic disorder versus True psychosomatic disorder , in order to distinguish the phenomenon that is routinely taken as a psychosomatic disorder, but that only indicates the psyche-soma intimate relationship, from the true psychosomatic disorder, in Winnicott?s concept, and the False psychosomatic disorder subcategories Natural reaction versus Pathological symptom , to separate natural physical manifestations of emotional difficulties from some kind of psychopathology, although not characterized as a real psychosomatic disorder. The genesis, dynamics and potential treatment of a psychosomatic symptom depends on the category it fits. By analyzing and systematizing the Winnicott material (work), we intended to contribute to deepening his theory and to solving the empiric-clinical problem of the psychosomatic phenomena. / Essa pesquisa objetivou explicitar a compreens?o que Winnicott teve dos problemas psicossom?ticos, principalmente em rela??o ? g?nese, din?mica e possibilidade de tratamento, contribuindo para o desenvolvimento de sua teoria psicossom?tica. Procurou-se reunir, organizar e classificar diversos casos e vinhetas cl?nicas, dispersos na obra de Winnicott, nos quais h? refer?ncia aos sintomas psicossom?ticos. A an?lise dos dados se deu a partir da rela??o desses com a teoria winnicottiana. A partir das no??es de Integra??o psiquesoma e Personaliza??o, Winnicott considera que o dist?rbio psicossom?tico verdadeiro est? relacionado com falhas em processos primitivos do desenvolvimento, e ressalta que o fen?meno que comumente ? chamado de dist?rbio psicossom?tico refere-se apenas ?s vincula??es entre o corpo e o psiquismo. Al?m disso, Winnicott afirma que, muitas vezes, as manifesta??es f?sicas advindas de dificuldades psicoemocionais s?o fen?menos naturais que fazem parte da vida e do processo de amadurecimento. Dessa forma, foram propostas as seguintes classifica??es para os casos e vinhetas cl?nicas: Falso dist?rbio psicossom?tico versus Verdadeiro dist?rbio psicossom?tico , com o intuito de diferenciar o fen?meno que corriqueiramente ? chamado de dist?rbio psicossom?tico, mas que apenas indica a ?ntima rela??o entre psique e soma, do dist?rbio psicossom?tico verdadeiro, na concep??o winnicottiana, e as subcategorias Rea??o natural versus Sintoma patol?gico , dentro da categoria Falso dist?rbio psicossom?tico , que indica que algumas manifesta??es f?sicas devem ser caracterizadas apenas como modos de se reagir ?s dificuldades inerentes ? vida, enquanto que outras indicam a presen?a de alguma psicopatologia, ainda que n?o se caracterize como um dist?rbio psicossom?tico verdadeiro. A g?nese, a din?mica e a forma de se tratar um problema psicossom?tico depende da categoria na qual ele se enquadre. Ao sistematizar e analisar esse material apresentado por Winnicott procurou-se contribuir para o aprofundamento de sua teoria e para a resolu??o do problema emp?rico-cl?nico dos fen?menos psicossom?ticos.
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The structure of ownership in family firms. / CUHK electronic theses & dissertations collection / Digital dissertation consortiumJanuary 2010 (has links)
Prior literature focuses on the causes and effects of ownership concentration between significant blockholders and minority shareholders. Anecdotal evidence shows that it is also important to look at the causes and effects of ownership concentration within controlling families as family ownership can become diffused after generations. Family trust is a popular vehicle for holding family ownership. It allows a founder to concentrate firm ownership on a long-term basis, preventing control loss after he/she steps down. Family members can enjoy control benefits such as preservation of their family intangible assets. However, there is tradeoff. Family members cannot resolve their conflicts by acquiring and selling off shares among them, since they are no longer the legal owners of the shares. / Using a sample of 216 family firms listed on the Hong Kong Stock Exchange with time series data spanning 1990--2008, I investigate the causes and effects of ownership concentration by means of family trust. I fmd that when family control is important (when there exists a large amount of family intangibles), there is a higher propensity that family trust is used to concentrate ownership and secure control, provided that the cost of using it is low (small family size hence low family conflict). However, when there are more and more family members after generations, the benefit of preserving the intangibles may not be high enough to cover the cost of potential family conflict, leading to firm value loss. Moreover, the cost of using trust magnifies during difficult periods such as financial distress, economic downturn and leadership succession. Hence, firms with high potential family conflict have poorer performance during difficult time if family trust is used for holding the firm's controlling stake. Family trust also induces common pool problem. Family members tend to extract resources from the family firm as much and as early as possible, leading to higher payout and slower firm growth. / Leung, Siu Ching. / Adviser: Joseph P. H. Fan. / Source: Dissertation Abstracts International, Volume: 73-03, Section: A, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaf 58). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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