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Diversidade de espécies arbóreas e sua relação com o histórico de perturbação antrópica em uma paisagem urbana da Floresta Atlântica / Tree species diversity and its relation with the history of anthropic disturbance in an urban landscape of the Atlantic ForestFonseca, Cassiano Ribeiro da 09 March 2017 (has links)
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Previous issue date: 2017-03-09 / O processo de urbanização é um dos maiores agentes de transformação da sociedade, com reflexos diretos na biodiversidade global. A maior expansão global da urbanização em ambientes naturais prevista até 2030 ocorrerá com a conversão de ambientes naturais em áreas urbanas na América do Sul. As alterações criadas pelo ambiente urbano fragmentam florestas, impedem sua conectividade, criam mudanças das condições microclimáticas, modificam o equilíbrio físico e biológico, deixando impactos diretos na estrutura, riqueza e também na diversidade dos ecossistemas florestais. Considerando a importância das florestas urbanas para a manutenção da biodiversidade, este estudo analisou como os padrões de diversidade alfa e beta variam nas comunidades de florestas urbanas, fazendo uma relação com seu histórico de perturbação. O estudo foi realizado na mesorregião da Zona da Mata Mineira na microrregião de Juiz de Fora, nas cidades de Juiz de Fora, Lima Duarte, Rio Preto e Santos Dumont. Foram amostrados todos os indivíduos arbóreos vivos (DAP ≥ 5 cm) em 12 trechos de florestas, sendo alocadas aleatoriamente 10 parcelas de 20 x 20 m, totalizando 120 parcelas, com área total amostrada de 4,8 ha. Os trechos foram classificados de acordo com os diferentes níveis de perturbação, históricos de impactos antrópicos, tipos de distúrbios e estrutura atual; e distribuídos em quatro ambientes florestais com características compartilhadas (controle, relicto, agricultura abandonada e terraplanagem). A partir dos resultados foi possível perceber um claro padrão de agrupamento entre os quatro ambientes florestais, os valores de riqueza, índices de diversidade e equabilidade, variaram de acordo com o grau de impacto sofrido, obtendo os maiores valores fragmentos mais preservados, e menores aqueles que sofreram os maiores impactos antrópicos. A análise da diversidade beta demonstrou baixo número de espécies compartilhadas, evidenciando grande heterogeneidade florística nos ambientes florestais urbanos. As análises de agrupamentos demonstraram que a estrutura dos ambientes florestais são o reflexo dos tipos e intensidades dos distúrbios causados pelo ambiente urbano, representadas na forma de grupos com grande autocorrelação. Apesar das grandes alterações construídas pelo ambiente urbano antrópico, ainda assim os fragmentos urbanos abrigam importante diversidade alfa e beta da flora arbórea regional. O conhecimento sobre a
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biodiversidade das florestas tropicais urbanas é fundamental para subsidiar ações de proteção, conservação e restauração da biota regional. / The urbanization process is one of the major agents in society transformation, with direct reflex on global biodiversity. The largest urbanization global expansion in natural environments, expected until 2030, will occur from the conversion of natural environments to urban areas in South America. The changes generated by urban settings fragment forests, hinder their connectivity, alter microclimate conditions and modify physical and biological balance, directly impacting on the structure, wealth and diversity of the forest ecosystem. Considering the importance of urban forests to the maintenance of biodiversity, this paper aims to analyze how alfa and beta diversity patterns vary in urban forest communities, relating to its disturbance history. The study took place in the mesoregion of Zona da Mata Mineira, in the microregion of Juiz de Fora, in the cities of Juiz de Fora, Lima Duarte, Rio Preto and Santos Dumont. All live arboreal individuals (DBH ≥ 5 cm) in twelve forest fragments were sampled, being 10 plots of 20 x 20m randomly allocated, totaling 120 plots. The fragments were classified according to the different levels of disturbance, history of human impact, types of disturbance and current structure; they were assorted in four forest settings with shared features (control, relict, abandoned agriculture and earthwork). From the results, it was possible to notice a clear pattern of grouping among the four forest settings; the values of wealth and diversity and equitability rates varied according to the impact endured, obtaining higher values in the most preserved fragments and lower in those which suffered with major human influence. The beta diversity analysis showed a low number of shared species, revealing great floristic heterogeneity in urban forest environments. The grouping analysis showed that forest environments reflect great changes caused by urban settings, depicted by groups with great autocorrelation. Regardless of alterations built by human urban settings, these urban fragments hold important alfa and beta diversity from the regional arboreal flora. Knowledge of urban rainforests biodiversity is essential to subsidize protection measures, preservation and recovery of regional biota.
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Reagentes de selênio e telúrio em síntese orgânica: íons de carbênio estalizados por selênio e alfa-telurocetonas / Selenium and Tellurium in Organic Synthesis: Carbenium Ions Stabilized of Selenium and Alfa-TeluroketonesHelio Alexandre Stefani 24 June 1988 (has links)
Na primeira parte deste trabalho, desenvolvemos duas metodologias para a preparação de α-dicloroteluro cetonas. A primeira utiliza a reação direta de tricloretos de ariltelúrio com cetonas e a segunda envolve a reação do mesmo reagente com éteres enólicos de silício de cetonas. As dicloroteluro cetonas preparadas foram transformadas em α-halo cetonas pela reação com cloro ou bromo, ou utilizando condições de termólise sob pressão reduzida. Dados de ressonância magnética nuclear de 1H e de 13C, de difração de raios-X e de espectros no infra-vermelho foram utilizados na determinação estrutural dos compostos preparados. Numa segunda arte foram preparados α-halo-α-seleno alcanos através da adição de HBr a selenetos vinílicos obtidos por reação de acetilenos aromáticos com selenofenol. Os α-halo-α-seleno alcanos foram transformados em α-selenofenil acetaldeídos por reação de solvólise em DMSO. / In the first parto of this work two methodologies for the synthesis of α-dichlorotelluroketones were developed. The first one employs the reaction of aryltellurium tricholorides with ketones and the second one involves the reaction of the same reagent with silylenol ethers of ketones. The α-dichlorotelluroketones prepared were transformed into α-halo ketones by means of the reaction with chlorine or bromine or by pyrolysis at reduced pressure. 1H and 13C nuclear magnetic ressonance, x-ray difraction and infrared data were used in the structure elucidations of the compounds prepared. In the second part of the work α-halo- α-seleno-alkanes were prepared by addition of hydrogen bromide to vinylic selenides which were prepared by reacting aromatic acetylenes with selenophenol. The α-halo-α-seleno-alkanes were transformed into α-selenophenyl acetaldehydes by solvolysis in DMSO.
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Análise da expressão das proteínas Rab anterior à agregação proteica associada a neurodegeneração / Analysis of Rab protein expression before protein aggregationThaiany Quevedo Melo 22 May 2012 (has links)
A neurodegeneração é um processo onde ocorre morte celular progressiva. O tráfego neuronal anterógrado e retrógado, e entre os compartimentos é essencial para a viabilidade celular. As proteínas Rabs pertencem à família de pequenas GTPases, com funções de tráfego de vesículas e organelas, para realizarem sua função as proteínas Rab podem recrutar proteínas motoras como as KIF 1B e KIF 5, responsáveis pelo transporte anterógrado mitocondrial. A associação do distúrbio do tráfego intracelular com doenças neurodegenerativas tem sido tema de estudos recentes. Com isso o objetivo do presente trabalho é analisar a expressão das proteínas Rab, bem como estudar as proteínas motoras que podem contribuir para o esclarecimento sobre os distúrbios no tráfego intracelular que antecedem a formação de agregados proteicos envolvidos em neurodegeneração. Para tanto, utilizou-se o modelo de tratamento com rotenona para indução de agregados em Ratos Lewis idosos que foram expostos a rotenona durante 4 semanas, em seguida foram avaliados os níveis de expressão das proteínas Rab no hipocampo, substância negra e locus coeruleus, por western blotting. Foram analisados também os níveis de expressão das proteínas motoras KIF1B e KIF5 antes e durante a formação de agregados proteicos, em culturas de células, de ratos Lewis neonatos, do hipocampo, substância negra e locus coeruleus tratadas com rotenona por 24 horas ou 48 horas nas concentrações de 0,1nM, 0, 3nM e 0,5nM. Foi observado diminuição dos níveis de expressão das proteínas Rab 1 nas regiões do hipocampo e locus coeruleus. Houve aumento de expressão das Rab 4,5 e 6 no hipocampo, porém na substância negra a expressão da Rab 1 aumentou e da Rab 6 diminuiu. Já no locus coeruleus in vivo a Rab 6 aumentou, mas as Rab 1, 5 e 11 diminuíram sua expressão. Já a expressão da KIF 5 aumentou com o tratamento de 0,1nM de rotenona e diminuiu após 0,5nM do xenobiótico por 48 horas in vitro, na mesma região. Na substância negra aumentaram as KIFs 1B e 5 após o tratamento com 0,5nM por 48 horas in vitro, mas diminuíram as KIF 1B e 5 após o tratamento com 0,3nM por 24 horas e KIF 5 após o tratamento com 0,1nM por 48 horas. Esses resultados permitem concluir que a expressão de proteínas importantes para o tráfego mitocondrial e de vesículas encontram-se alteradas e fazem parte dos eventos intracelulares que antecedem a neurodegeneração / Neurodegeneration is a process that leads to progressive cell death. The anterograde and retrograde neuronal traffic as well as the traffic between compartments are essential for cell viability. The Rab proteins belong to the small GTPases family with function of vesicles and organelle trafficking. Rab proteins can recruit motor proteins such as KIF 1B and KIF 5 that are responsible for anterograde mitochondrial transport. The association of intracellular traffic disturb with neurodegenerative diseases have been theme of recent studies. Thereat the objective of this study is analyze the expression of Rab and motor proteins that can contribute for the understanding about the disturb of the intracellular traffic that precedes protein aggregation involved in neurodegeneration. For this purpose it was employed the model of rotenone treatment for induction of aggregation in aged Lewis rats that were exposed to rotenone during 4 weeks in order to evaluate Rabs expression. The levels of motor proteins KIF 1B and KIF 5 expression were evaluated before and during the formation of protein aggregates in hippocampus, substantia nigra and locus coeruleus cell cultures of neonates Lewis rats, exposed to rotenone for 24 hours or 48 hours in the concentrations of 0.1nM, 0.3nM or 0.5nM. It was observed decreased levels of Rab 1 expression in hippocampus and locus coeruleus. Rabs 4,5 and 6 were increased in the hippocampus, but in the substantia nigra the expression of Rab 1 increased and Rab 6 decreased. In the locus coeruleus the Rab 6 increased, but Rabs 1, 5 and 11 decreased. The expression of KIF 5 increased after 0.1nM of rotenone and decreased after the exposure to 0.5nM of for 48 hours in cultured cell from the locus coeruleus. In the substantia nigra the KIF1B and KIF 5 increased after treatment with 0.5nM for 48 hours in vitro, but these protein decreased after treatment with 0.3nM for 24 hours in vitro, and KIF 5 after treatment with 0.1nM for 48 hours. These results allow us conclude that the expression of important proteins for the mitochondrial and vesicles traffic are altered and participate of intracellular events that precede the neurodegeneration
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Demonstrační úloha pro robotický manipulátor EPSON / Demonstration Application for EPSON Industrial ManipulatorFireš, Martin January 2012 (has links)
This work deals with design and construction of a robotics checkers player based on computer vision, a move solving algorithm Minimax and a industrial manipulator EPSON C3. Work also deals with design of robot communication protocol and C# communication library execution.
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Äetn, daov© a legislativn aspekty konkurzu na pkladu vybran© firmy / Bankruptcy and its fiscal, bookkeeping, legislature aspects in the Selected FirmGrulichov, Jana January 2007 (has links)
This master thesis describes the course of bankruptcy proceedings. The teoretical part deals with both approaches to bankruptcy proceedings and tax and accounting impacts on a company in bankruptcy. The practical part concentrates on a real insolvent company with articulating possibilities for prevention of the insolvency. Next, it suggests an effective realization of assets in bankruptcy.
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Technická analýza / Technical AnalysisOndrušová, Denisa January 2012 (has links)
This master‘s thesis is focused on creating an application, which would suggest an optimal portfolio of shares from SPAD Stock Market Praha. The application is based on the CAPM model, which is also described in this paper. There is a calculation of securities characteristics and specific portfolio diversification is suggested. The application also allows a user to simulate investments based on his requirements.
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Psychische Belastungsfaktoren bei Patienten mit chronischer Hepatitis-C-Infektion während und außerhalb einer antiviralen InterferontherapieSchäfer, Arne 31 January 2008 (has links)
I) Hintergrund Die chronische Hepatitis-C-Infektion stellt global ein wesentliches Gesundheitsproblem dar. Diese Virusinfektion kann bei unbehandelten Patienten zur Leberzirrhose und im weiteren Verlauf bis hin zur Entwicklung eines hepatozellulären Karzinoms führen. Die einzige Behandlungsoption mit der Aussicht auf dauerhafte Viruselimination besteht in modernen Kombinationstherapien, die das Zytokin Interferon alfa enthalten. Wesentliche Merkmale sind – neben inzwischen sehr hohen Ansprechraten – eine Behandlungsdauer zwischen 24 und 48 Wochen, hohe Therapiekosten und ein Nebenwirkungsprofil, das sowohl somatische als auch psychopathologische Symptome umfassen kann. II) Untersuchungsgegenstand und Fragestellungen Sowohl die chronische Virusinfektion an sich als auch die aktuell verfügbaren Therapieverfahren bergen ein erhebliches psychisches Belastungspotential. Hauptgegenstand dieser Dissertation ist die Erfassung der psychologischen Aspekte der Erkrankung und der psychischen und psychopathologischen Nebenwirkungen einer Interferonbehandlung. Wesentliche bearbeitete Fragestellungen sind: - Welchen Belastungsfaktoren sind Hepatitis-C-Patienten bereits ohne aktuelle antivirale Interferontherapie ausgesetzt bzw. welche psychopathologischen Symptome zeigen diese Patienten? - Wie ist der zeitliche Verlauf psychopathologischer Symptome bei Hepatitis-C-Patienten vor, während und nach einer antiviralen Therapie? - Wie wirksam und wie sicher ist eine medikamentöse Behandlung der Interferon-induzierten Depression mit selektiven Serotonin-Wiederaufnahmehemmern (SSRI) unter Fortführung der antiviralen Therapie? III) Patienten und Methoden Studienteilnehmer waren Hepatitis-C-Patienten, die sich ambulant vorstellten bzw. in unsere Ambulanz überwiesen wurden und die jeweiligen Einschlusskriterien erfüllten. Zu den wichtigsten verwendeten psychometrischen Selbstbeurteilungsskalen zählen: HADS (Depressivität, Angst), SCL-90-R (psychopathologische Symptome), SF-36 (Lebensqualität) und FKV (Krankheitsverarbeitung). IV) Wesentliche Forschungsergebnisse Bereits ohne Einfluss des Zytokins Interferon bestehen starke Krankheits-assoziierte psychische bzw. psychosoziale Belastungen der Patienten, die sich in einem erhöhten Depressionsrisiko ausdrücken. Die erhobenen Depressionsscores stehen in signifikantem Zusammenhang mit der Erkrankungsdauer und den individuell bestehenden Optionen und Erfolgsaussichten einer antiviralen Interferontherapie. Prospektive Erfassungen der Auftretenshäufigkeit klinisch relevanter Interferon-assoziierter Depressionen ergeben Raten von ca. 30 %. Diese Größenordnung wurde sowohl in einer eigenen prospektiven Studie als auch im Rahmen einer vorgestellten Übersichtsarbeit bestätigt. Die Umstellung der verwendeten Formulierung des Medikaments von herkömmlichem Interferon alfa auf die pegylierte Variante brachte keine Verbesserung der Verträglichkeit z.B. im Hinblick auf die interferonassoziierte Depression. Ein rechtzeitiges Erkennen der entsprechenden Symptome vorausgesetzt, ist die antidepressive Behandlung der Interferon-assoziierten Depression mit Hilfe von selektiven Serotonin-Reuptake-Inhibitoren auch ohne generelle Prophylaxe sehr effektiv und sicher möglich. V) Diskussion Empfohlen wird ein engmaschiges psychometrisches Monitoring aller Hepatitis-C-Patienten im Therapieverlauf. Ausführliche Aufklärung, enger Arzt-Patienten-Kontakt während der Therapie, sowie die Betreuung durch einen festen Ansprechpartner während der bis zu einem Jahr dauernden Therapie sind wichtige Rahmenbedingungen für eine solche Behandlung. Für die medikamentöse Behandlung der Interferon-induzierten Depression gilt: Bei besonderer Indikation (z.B. Interferon-assoziierte Depression bei früheren Therapieversuchen) sollte eine SSRI-Sekundärprophylaxe in Betracht gezogen werden. Ansonsten ist eine entsprechende SSRI-Intervention beginnend mit dem Einsetzen einer klinisch relevanten Depression ausreichend.
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Morningstar Ratings, Mutual Fund Flows and Performance : Investigating the Swedish Domestic Fund Market / Morningstar Ratings, fondflöden och prestandaOHLSSON, DAVID January 2021 (has links)
Morningstar ratings are a popular way for investors to compare mutual funds. This thesis focuses on Swedish domestic equity funds. The relation of Morningstar ratings and fund flows was studied. Additionally, the short-term performance predictability using star ratings was investigated. This study found that top rated funds using Morningstar ratings received a higher fraction of positive fund flows compared to top rated funds ranked using past returns, Sharpe ratio, or Carhart's four-factor alpha. This provides some evidence towards Swedish investors using Morningstar ratings over other measures when selecting mutual funds. Additionally, all four measures performed poorly when used to predict one-, three- and twelve-month future fund flows, with no model being able to explain more than 7% of the variance in the data (measured in adjusted R-squared). Finally, the predictive power of Morningstar rating in respect to future outperformance (measured in Carhart's four-factor alpha) was evaluated. While all star ratings were statistically significant predictors, no model managed to explain more than 17% of the data's variance. Thus, Morningstar ratings were not found to be a good predictor of future outperformance. / Morningstar Ratings är ett populärt sätt för investerare att jämföra fonder. Denna uppsats fokuserar på svenska fonder som investerar på den svenska aktiemarknaden. Sambandet mellan Morningstar Ratings och fondflöden studerades. Även förmågan att på kort sikt förutsäga fonders prestation genom att använda deras Morningstar Rating undersöktes. Denna studie fann att topprankade fonder utifrån Morningstars prestationsmått fick en högre andel av positiva inflöden än om fonderna rankades efter tidigare avkastning, Sharpekvot eller Carharts alfa. Detta ger begränsat stöd till att svenska investerare använder Morningstar Ratings över andra prestationsmått vid val av fonder. Dessutom hade alla mått låg förklarande förmåga för framtida fondflöden över en, tre och tolv månader. Ingen modell kunde förklara mer än 7% av variansen i fondflödena (mätt i justerad R2). Till sist utvärderades förmågan att förutsäga framtida (Carharts) alfa genom Morningstar Rating. Trots att Morningstar Ratings kunde anses vara statistiskt viktiga för modellen, lyckades ingen modell förklara mer än 17% av variansen i alfa. Således kunde inte Morningstar Ratings anses vara en bra prediktor för framtida alfa.
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Transkranijinės magnetinės stimuliacijos įtaka galvos smegenų bioelektriniam aktyvumui / Effects of transcranial magnetic stimulation on bioelectrical brain activityVištartaitė, Giedrė 27 June 2014 (has links)
Šio darbo metu tirta skirtingų rTMS parametrų įtaka galvos smegenų bioelektriniam aktyvumui. Atlikus EEG duomenų spektrinę analizę, pademonstruota, jog aukšto dažnio rTMS virš KPFDLŽ, skirtingai nuo žemo dažnio rTMS virš DPFDLŽ, stimuliuojant aštuoniukės formos rite, statistiškai patikimai padidina alfa bangų dažnių diapazono absoliučią galią dešiniajame pusrutulyje. Paminėtina ir tai, kad po gydymo kurso rTMS aštuoniukės formos rite Kleino protokolu, skirtingai nei klasikiniu protokolu, frontalinėje srityje alfa bangų dažnio diapazone statistiškai reikšmingai sumažėja (F7-F8)/(F7+F8) asimetrijos koeficientas. Svarbu pažymėti, jog po rTMS stimuliacijos apvalia rite, palyginus su stimuliacija aštuoniukės formos rite, registruojami labiau išplitę, sudėtingesni smegenų bioelektrinio aktyvumo pokyčiai. / Recently rTMS emerged as a new clinical tool for the treatment of major depressive disorder. rTMS is noninvasive and easily tolerated method that is able to alter bioelectrical brain activity. This phenomenon is achieved by using alternating magnetic fields to induce electric currents in cortical tissue. Nowadays it is widelly accepted that lateralized alterations in brain activity might play a role in depressive symptoms. It has been found that major depressive disorder patients exhibit greater right frontal activity in contrast to left frontal hypoactivation (it should be noted, that cortical activity is inversely related with alpha power). Therefore rTMS is a potential method that can help to re-eastablish normal brain activity. In this study we examined effects of different rTMS parameters (protocols and stimulation coils) on bioelectrical brain activity modulation in patients with the treatment resistant major depressive disorder. It was shown that 10 Hz stimulation with the figure-eight coil over the left prefrontal area increases alpha power in the right hemisphere. In addition, it was demonstrated that 1 Hz stimulation over the left prefrontal cortex changes frontal alpha asymmetry. It should be underlined, that there appears to be no significant difference in clinical efficacy between the two protocols. It was also demonstrated that changes in frontal alpha asymmetry tend to correlate with the outcome of the treatment. Furthermore, it was shown that stimulation with... [to full text]
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Vztah obsahu helia ve slunečním větru k procesům na Slunci / Relationship of helium abundance in the solar wind to solar activityCagaš, Petr January 2015 (has links)
Rapid changes in relative helium abundance in solar wind are often attributed to the flux tube crossings - thus between solar wind streams coming from different parts of the solar corona. Recent studies however show, that the changes in relative helium abundance are not always correlated with changes in other parameters and therefore the relative helium abundance could be changed even during the propagation of solar wind inside a flux tube. The topic of this thesis is an analysis of rapid changes of solar wind parameters and their mutual connection. Using a multipoint (we use data from the SPEKTR-R, WIND and the THEMIS spacecraft) case study of interplanetary shocks, we show that a possible explanation of those changes could be a magnetosonic instability excited by the differential flow between helium and proton populations.
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