Made available in DSpace on 2015-03-26T13:39:47Z (GMT). No. of bitstreams: 1 texto completo.pdf: 739809 bytes, checksum: 69524346956f11b5bb2a849577857347 (MD5) Previous issue date: 2012-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The competitive ability of crops and weeds is related to the efficient use of environmental resources. However, it may also be related to the associations of these species with soil microbiota and the ability to change it to minimize interference. The objective of this study was to evaluate the effects of the interference of five weeds in dry matter accumulation of corn plants and in the relative content of nutrients, as well as evaluate the biomass and microbial activity associated with weeds and corn in monoculture and in competition, in soils with diferent fertility managements. The experiment was conducted in a protected environment, considering four soil fertility managements (with calcium and magnesium silicate and fertilization; with limestone and fertilization; without correction of acidity, but with fertilization; without correction of acidity and without fertilization) and five arrangements competition between Zea mays and the weeds Brachiaria brizantha, Ipomoea grandifolia, Conyza canadensis, Bidens pilosa and Hyptis suaveolens, addition of species in monoculture and soils without plants. The coexistence of corn with weeds caused average reductions of 43.9%, 39.8% and 41.9% in dry matter of shoot, root and total culture, respectively. Under interference of B. brizantha, the corn had reductions exceeding 50% in the content of all macronutrients, being this weed the most damaging to the culture. Additionally, B. brizantha and B. pilosa in competition with corn stood out among the other weeds and has high ability to extract and use macronutrients in the four soil conditions. There was a tendency of reduction of microbial biomass carbon (MBC) in soils that receive were not correction acidity. B. pilosa and the arrangement formed by Z. mays and B. brizantha, showed high values of MBC, regardless of soil management. Low biological activity was observed in soil without acidity correction and without fertilization. In soil with calcium and magnesium silicate and maize plants in monoculture, the metabolic quotient (qCO2) was higher than the value observed with the weeds in monoculture and in competition arrangements, suggesting greater susceptibility of this system for carbon losses. Z. mays in competition with H. suaveolens was the arrangement that had greater preservation of organic matter (<qCO2) in the four soils. The weeds showed different competitive abilities causing reductions in the dry matter and nutrients accumulation in the corn plants, and showed distinct potential for nutrient cycling, depending on soil condition. Calcium and magnesium silicate and limestone did not differ in the weed interference on the dry biomass of corn plants, being the influence of these sources variable on nutrient accumulation by plants in monoculture or under interference. The microbial biomass and activity were altered by plant species, interference and managements of soil fertility. The manipulation of soil microorganisms may be a strategy used by corn and, or the weeds to minimize the competition in a given soil. / A habilidade competitiva das culturas e das plantas daninhas está relacionada à utilização eficiente dos recursos do meio na qual se encontram. No entanto, pode também estar relacionada com as associações dessas espécies com a microbiota do solo e a capacidade de alterá-la para minimizar a interferência. Objetivou-se com este trabalho avaliar os efeitos da interferência de cinco plantas daninhas no acúmulo de matéria seca e no conteúdo relativo de macronutrientes de plantas de milho, bem como a biomassa e a atividade microbiana associada às plantas daninhas e de milho em monocultivo e em competição, em solos com diferentes manejos de fertilidade. O experimento foi realizado em casa de vegetação, considerando-se como primeiro fator quatro manejos de fertilidade do solo (com silicato de cálcio e magnésio e adubação; com calcário e adubação; sem correção de acidez, mas com adubação; sem correção de acidez e sem adubação) e como segundo fator cinco arranjos de competição entre Zea mays e as plantas daninhas Brachiaria brizantha, Ipomoea grandifolia, Conyza canadensis, Hyptis suaveolens e Bidens pilosa, acrescido das seis espécies em monocultivo e de solo sem cultivo. A convivência do milho com plantas daninhas provocou reduções médias de 43,9%, 39,8% e 41,9% na massa da matéria seca da parte aérea, do sistema radicular e total da cultura, respectivamente. Sob interferência de B. brizantha, o milho apresentou reduções superiores a 50% no conteúdo de todos os macronutrientes, sendo esta a planta daninha mais danosa a cultura. Adicionalmente, B. brizantha e B. pilosa em competição com o milho se destacaram entre as demais plantas daninhas, apresentando elevada habilidade de extração e utilização de macronutrientes nas quatro condições de solo. Observou-se tendência de redução do carbono da biomassa microbina (CBM) nos solos que não tiveram correção de acidez. B. pilosa e o arranjo formado por Z. mays e B. brinzantha, independente do solo, apresentaram elevados valores de CBM. Baixa atividade biológica foi verificada no solo sem correção de acidez e sem adubação. No solo corrigido com silicato de cálcio e magnésio e cultivado com milho livre de interferência, o quociente metabólico (qCO2) foi maior do que com as plantas daninhas em monocultivo e arranjos de competição, sugerindo maior suscetibilidade desse sistema a perdas de carbono. Z. mays em competição com H. suaveolens mostrou ser o sistema misto mais conservativo da matéria orgânica (<qCO2) nos quatro manejos de fertilidade do solo. As plantas daninhas apresentaram não só habilidades competitivas distintas, provocando reduções consideráveis no acúmulo de matéria seca e nutrientes das plantas de milho, como também potencial diferenciado para ciclagem dos nutrientes estudados, a depender da condição de solo. Silicato de cálcio e magnésio e calcário não diferiram quanto à interferência das plantas daninhas sobre o acúmulo de biomassa seca das plantas de milho, sendo variável a influência dessas fontes sobre o acúmulo de nutrientes pelas plantas em monocultivo ou sob interferência. A biomassa e atividade microbiana foram alteradas pelas espécies de plantas, pela convivência e pelos manejos de fertilidade do solo, e a manipulação dos microrganismos do solo pode ser uma estratégia utilizada pela cultura do milho e, ou pelas plantas daninhas para minimizar a competição em determinado ambiente.

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Quasi-hom-Lie algebras (qhl-algebras) were introduced by Larsson and Silvestrov (2004) as a generalisation of hom-Lie algebras, which are a deformation of Lie algebras. Lie algebras are defined by an operation called bracket, [·,·], and a three-term Jacobi identity. By the theorem from Hartwig, Larsson, and Silvestrov (2003), this bracket and the three-term Jacobi identity are deformed into a new bracket operation, &lt;·,·&gt;, and a six-term Jacobi identity, making it a quasi-hom-Lie algebra. Throughout this thesis we deform the Lie algebra sl2(F), where F is a field of characteristic 0. We examine the quasi-deformed relations and six-term Jacobi identities of the following polynomial algebras: F[t], F[t]/(t2), F[t]/(t3), F[t]/(t4), F[t]/(t5), F[t]/(tn), where n is a positive integer ≥2, and F[t]/((t-t0)3). Larsson and Silvestrov (2005) and Larsson, Sigurdsson, and Silvestrov (2008) have already examined some of these cases, which we repeat for the reader's convenience. We further investigate the following σ-twisted derivations, and how they act in the different cases of mentioned polynomial algebras: the ordinary differential operator, the shifted difference operator, the Jackson q-derivation operator, the continuous q-difference operator, the Eulerian operator, the divided difference operator, and the nilpotent imaginary derivative operator. We also introduce a new, general, σ-twisted derivation operator, which is σ(t) as a polynomial of degree k.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A cyclic code is a speci c type of linear code. Its relevance consists in the fact that all its main information is intrinsic to the structure of the ideals in the quotient ring K[x]=(xn - 1) via an isomorphism. In this work, we characterize the cyclic codes in biunivocal correspondence with the ideals of this quotient ring. We will also present its generating matrix, the parity matrix and we will discuss its codi cation and decoding. / Um código cíclico é um tipo específico de código linear. Sua relevância consiste no fato de que todas suas principais informações são intrinsecas à estrutura dos ideais no anel quociente K[x]=(xn 1) via um isomorfismo. Neste trabalho, caracterizamos os códigos cíclicos em correspondência biunívoca com os ideais deste anel quociente. Apresentaremos também sua matriz geradora, a matriz de paridade e abordaremos sua codificação e decodificação.

Azidotische Belastungen des Pansens gelten bei Milchkühen besonders in der Frühlaktation als weit verbreitet. Sie werden als subakute Pansenazidosen (SARA) für die häufigen Produktionskrankheiten verantwortlich gemacht. Ziele : dieser Untersuchungen waren a) die Kontrolle des Säure-Basen-Haushalt (SBH) bei HF- Hochleistungskühen im peripartalen Zeitraum zum Vorkommen von SARA, b) die Prüfung bewährter sowie neuer Methoden zur Pansensaftanalyse, c) die Analyse von SBH-Harnparametern sowie d) die Prüfung möglicher Beziehungen von Stoffwechselparametern im Blut zu SBH-Parametern im Pansensaft. Versuchsanordnung : In 10 Betrieben Niedersachsens wurden an je 10 Kühen Verlaufsuntersuchungen mit vier Proben/Tier durchgeführt: 1. Trockenstehperiode/Färsen -30 Tage ante partum (d a.p.) bis zur Kalbung; 2. 2 bis 7 Tage post partum (d p.p.); 3. in der Frühlaktation 8 bis 30 d p.p. und 4. in der Mittellaktation 80 bis 150 d p.p. Pansensaft vormittags mit Geishauser- Sonde gewonnen, Blut aus der V. jugularis externa sowie Harn per Blasenkathederisierung. Analysiert wurden im Pansensaft der pH-Wert, die Pufferkapazität als Titrationsbilanz über die Titrationsazidität und - alkalität, die Methylenblauprobe sowie die Sedimentaktivitätszeit (SAT), im Harn der pH-Wert, die Netto-Säure-Basen-Ausscheidung (NSBA) sowie der Basen-Säure-Quotient (BSQ) und im Blutserum Glukose, freie Fettsäuren (FFS), Betahydroxybutyrat (BHB), L-Laktat, Cholesterol, Protein, Albumin, Bilirubin, Harnstoff, Kreatinin, Na, K, Cl, Ca, P, Mg, ALP, ASAT, GLDH sowie die CK. Ergebnisse: Zwischen Kühen und Färsen wurden bei den gemessenen Parametern keine gesicherten Unterschiede festgestellt. Es gab auch keine Unterschiede zwischen den Betrieben. Die Pansen-pH-Werte bewegten sich von x= 6,8 (6,43/7,0;1./3. Quartil) zu Beginn des Trockenstehens über minimal x = 6,3 (5,9/6,7) 30 bis 60 d p.p. bis x = 6,6 (6,2/6,8) in der Mittellaktation. Sie lagen alle im physiologischen Bereich. 20 Kühe hatten Pansen-pH-Werte von < 5,8, 6 Kühe von < 5,5 und 21 Kühe von > 7,2. Damit kamen die Kühe der SARA-Definition, bezogen auf das einmalige Auftreten von pH-Werten < 5,8 bei einer Kuh, nahe; bezogen auf alle gemessenen Pansen-pH-Werte betrug der Anteil < 5,8 aber nur 9,8 %. Die Titrationsbilanz war in der Trockensteherperiode ausgeglichen; bei allen drei Kontrollen p.p. bestand ein Basendefizit. Die Pufferkapazität war in der 1. Woche p.p. und in der Frühlaktation vermindert. Panse-pH-Werte und Titrationsbilanz korrelierten sehr eng (r=0,98,p<0,001). Die Methylenblauprobe war a.p. mit x = 3:37 (2:22/4:59) Minuten am längsten, in der Mittellaktation mit 3:01 (2:25/4:30) Minuten am kürzesten und ingesamt physiologisch. Es gab keine signifikanten Unterschiede zwischen den einzelnen Kontollzeiträumen. Die SAT war physiologisch und schwankte zwischen zwei und fünf Minuten ohne signifikante Unterschiede zwischen den Entnahmezeiträumen. Im Harn lagen die NSBA mit x = 70 mmol/l (20/122 = 1./3.Quartil) und der BSQ mit x = 2,2 (1,6/2,8) nur bei den Frischmelkern unter den unteren Grenzwerten und deuteten die Gefahr von SARA an. Der Harn-pH-Wert war mit x = 7,98 (7,7/8,2) physiologisch. Von der Gesamtheit alle NSBA-Werte waren 37% < 83 mmol/l sowie 28,9% < 25 mmol/l; beim BSQ waren es 52,6% < 2,5 sowie 27,4% < 1,5. Die für die NSBA, den BSQ und den Harn-pH-Wert berechneten Sensivitäten und Spezifitäten für einen Pansen-pH-Wert < 5,8 liegen mit 44,8% und 64,5% (NSBA), 55,8% und 47,9% (BSQ) sowie 2,3% und 97% (Harn-pH-Wert) unter den diagnostischen Erfordernissen.Sie können somit keine sicheren Rückschlüsse auf den Pansenzustand geben. Bei den Blutbefunden wurden Kühe mit Pansen-pH-Werten < 5,8 (SARA) und >5,8 gegenüber gestellt. Die Korrelationskoeffizienten, die Sensitivität und die mittels Receiver-Operating-Characteristics Analysen ermittelten Flächen unter der Kurve zwischen Pansen-pH-Wert und den Blutparametern waren niedrig ( p> 0,05). Schlussfolgerung: Hochleistende HF-Kühe haben peripartal nicht zwangsläufig eine SARA. Die Titrationsbilanz ergänzt den Pansensaft-pH-Wert, ist routinemäßig aber nicht nötig. Im Harn liegen die NSBA und BSQ häufiger unter den Grenzwerten und korrelieren nicht gesichert mit dem Pansen-pH-Wert. Auch Blutparameter erlauben keine sichere Aussage über den Pansenzustand. Die Diagnose von SARA muss mit direkter Messung des Pansen-pH-Wertes gestellt werden.

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Fetal Alcohol Syndrome (FAS) is a preventable cause of mental retardation and is the severest category within Fetal Alcohol Spectrum Disorder (FASD). As gestational alcohol exposure affects fetal cognitive functioning, children with FAS present with intellectual deficits. Unfortunately FASD prevalence rates are increasing amongst infants and school-going children. The main goal of this study was to compare the neurodevelopmental subscales of infants diagnosed with FAS, Partial FAS and non- FAS. Seventy-four infants with confirmed FAS, Partial FAS or Non- FAS diagnoses were assessed using the Griffiths Mental Developmental Scale. Development assessed at 7-12 and 17-29 months of age showed that, regardless of a FAS, PFAS or Non-FAS diagnosis, all infants performed weaker at their assessment at 17-29 months. The Subscales significantly affected included Personal-Social, Eye- Hand Coordination and Performance. The infants with FAS and PFAS displayed the most marked developmental delays. From this study it can be concluded that there are definite neurodevelopmental profiles for infant's diagnosed with FAS, PFAS and/or Non-FAS, highlighting the significant impact of prenatal alcohol exposure on various aspects of infant development. / Social work / M.Diac.