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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.
41

Doses de nitrogênio na cultura antecessora e do milho em sistema plantio direto

Nascimento, Flavia Meinicke [UNESP] 31 January 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-01-31Bitstream added on 2014-06-13T19:52:15Z : No. of bitstreams: 1 nascimento_fm_me_botfca.pdf: 672188 bytes, checksum: 48e970a9e0a259e419f9a68daaa916db (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O aumento do emprego do Sistema Plantio Direto, no Brasil, tem revelado de maneira inquestionável a necessidade do aprofundamento das pesquisas que avaliem os efeitos das culturas antecessoras sobre culturas de gramíneas anuais, particularmente na cultura do milho. A presente pesquisa teve como objetivo avaliar a resposta da cultura do milho em sucessão às culturas de soja + aveia e milho + aveia, havendo a antecipação da aplicação do nitrogênio na cultura da aveia, em doses crescentes, no Sistema Plantio Direto. Foram conduzidos dois experimentos em condições de campo em solo classificado como NITOSSOLO VERMELHO distroférrico, na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas da UNESP, Campus de Botucatu. No experimento nº1, foi realizada a seguinte sucessão de culturas: soja, aveia e milho; enquanto no experimento nº2, a sucessão de culturas foi: milho, aveia e milho. Nos dois experimentos foram consideradas parcelas as doses de nitrogênio aplicadas na cultura da aveia: 0, 20, 40 e 60 kg ha-1. As doses de nitrogênio aplicadas em cobertura na cultura do milho, foram consideradas subparcelas, variando nas seguintes doses: 60, 80, 100 e 120 kg ha-1, aplicados de forma parcelada em dois estádios da cultura do milho, a saber: 1ª aplicação no estádio de 3 a 4 folhas totalmente distendidas e a 2ª aplicação no estádio de 6 a 7 folhas totalmente distendidas. Na cultura da aveia foi avaliada a massa de matéria seca e calculada a relação C/N. Na cultura do milho foi calculada a relação C/N, quantificado o nitrogênio na planta antes da primeira cobertura e quinze dias após a aplicação da segunda cobertura, sendo nesta coeficientes de determinação (R2) tiveram sua significância testada ao nível de 5% de probabilidade e considerados significativos quando R2 foi superior a 60%. Os experimentos foram analisados estatísticamente separados... / The growing use of no–tillage system, in Brazil, has unquestionably revealed the need of deeper investigation to assess the effects of preceding cultures on current annual grass cultures, specially the corn ones. The main goal of this current research is to evaluate the response of corn plantation in succession on cultures of soybean + black oat and corn + black oat, with the antecipation of nitrogen applications in the black oat culture, in increasing doses, in no–tillage system. Two experiments in field conditions in soils classified as NITOSSOLO VERMELHO distroférrico were conducted, on Lageado Experimental Farm, at Faculdade de Ciências Agronômicas of UNESP, Botucatu Campus. On experiment nº1, the succession was conducted as follows: soybean, black oat and corn while on experiment nº2 the culture succession was: corn, black oat and corn. On both experiments, parcels of 0, 20, 40 e 60 kg ha-1 of nitrogen doses were applied on the black oat cultures. In relation to the corn cultures, subparcels were considered, varying on the following doses: 60, 80, 100 e 120 kg ha-1. The latter were applied gradually in two stages of the corn culture, as follows: 1st application on the stage of 3 to 4 totally unfolded leaves and the 2nd application on the stage of 6 to 7 totally unfolded leaves. On the black oat culture, the dry matter mass was assessed and the relation C/N calculated. On the corn culture the relation of C/N was also calculated; the nitrogen in the plants was quantified before the first covering and 15 days after the second At the end of the cicle, the plant and the first spike insertion heights and the stem diameter were measured and the spike indexes were calculated. After the harvest, the number of rows per spike was counted, the mass of 1000 grains was measured and the productivity was calculated. The data were submitted to the variance analysis and compared through the F test...(Complete abstract, click electronic access below)
42

Modifikace povrchových vlastností plasmatem u semen / Seeds surface plasma modification

HRUŠKOVÁ, Iveta January 2009 (has links)
Aim of diploma work is research of plasma influence on seed germination in some plant species (wheat and oat). The complex work includes parts both physical-technological and biological. The work discusses a selection of useful seeds for the plasma treatment and describes parameters of plasma processing. It discusses results of germination testing and early growth of seedlings. Parts of the work are electron microscopy output, data processing result, and appendix.
43

Applying Bioinformatic Techniques to Identify Cold-associated Genes in Oat

Thorburn, Henrik January 2002 (has links)
As the interest in biological sequence analysis increases, more efficient techniques to sequence, map and analyse genome data are needed. One frequently used technique is EST sequencing, which has proven to be a fast and cheap method to extract genome data. An EST sequencing generates large numbers of low-quality sequences which have to be managed and analysed further. Performing complete searches and finding guaranteed results are very time consuming. This dissertation project presents a method that can be used to perform rapid gene prediction of function-specific genes in EST data, as well as the results and an estimation of the accuracy of the method. This dissertation project applies various methods and techniques on actual data, attempting to identify genes involved in cold-associative processes in plants. The presented method consists of three steps. First, a database with genes known to have cold-associated properties is assembled. These genes are extracted from other, already sequenced and analysed organisms. Secondly, this database is used to identify homologues in an unanalysed EST dataset, generating a candidate-list of cold-associated genes. Last, each of the identified candidate cold-associative genes are verified, both to estimate the accuracy of the rapid gene prediction and also to support the removal of candidates which are not cold-associative. The method was applied to a previously unanalysed Avena sativa EST dataset, and was able to identify 135 candidate genes from approximately 9500 EST's. Out of these, 103 were verified as cold-associated genes.
44

Gas evolution of corn kernels, oat hulls, and paper sludge from biomass gasification

Ulstad, James Steven 01 December 2010 (has links)
Gasification of biomass has become an area of key interest as it is a reasonably quick and direct way of converting material into a fuel source that works in many industrial systems. The purpose of the present work is to explore biomass gasification and in particular pyrolysis behavior of corn kernels, oat hulls, and paper sludge. For the materials, low temperature gasification behavior was studied. Here, tests were performed with pyrolysis temperatures from 400 - 800°C, at 1 atm and a rapid heating rate. A small concentration of O2 was added to the gasification agent (N2) to enhance CO yields, similar to modern industrial gasifiers. The evolution of CO, CO2, CH4, H2, and O2 were measured throughout the pyrolysis process. Results show a direct correlation between temperature and the composition of the gas byproduct for all biomasses. CO production increases with an increase in temperature while CO2 shows no temperature correlation. O2 depletion mimics the CO evolution and increases with an increase in temperature. CH4 production was observed, however the results were rarely repeatable due to the sensor's sensitivity to moisture and tar in the gas byproduct. No hydrogen was observed, as would be expected for the short experimental residence time (0.2 seconds).
45

Characterization and Variable Expression of the CslF6 Homologs in Oat (Avena sp.)

Coon, Melissa A. 09 August 2012 (has links) (PDF)
(1,3;1,4)-β- D-glucan (β-glucan) is a plant cell wall hemicellulose and a main component of endosperm cell walls. The Cellulose Synthase F family of genes is involved in the synthesis of β-glucan. In this study full-length genomic sequences of CslF6 were obtained from multiple Avena species. Three unique alleles were found in each A. sativa line. Comparisons of these alleles to diploid Avena species allowed for identification of the genomic origin of each allele. The A and D genome alleles had identical amino acid sequences while the C-genome had 13 different amino acids. Global expression of CslF6 was completed at three developmental time point and three tissue types. RNAseq technology was utilized to determine genome specific expression patterns. Differential expression of genome specific-copies of CslF6 was found at all time points tested. Lower levels of C-genome expression of CslF6 were associated with increased levels of B-glucan.
46

Tvorba výnosu nahých a pluchatých odrůd ovsa / The yield formation of naked and hulled oats

FIŠER, Martin January 2016 (has links)
The aim of the thesis was to assess the formation and reduction in the yield of naked and hulled oat varieties. The research was conducted two years and it was mainly focused on the main elements of income as a number of plants, cuttings, and lat per m2, further was assessed the number of grains per panicle 1, weight of thousand grains and total grain yield. As an additional assessment of quality indicators have been established; volume weight and the proportion of grains of the front. The values of determined individual elements have been compared to each other and evaluated by statistical analysis. The results based on the naked oat varieties attain average yields of grain; diameter compared varieties of naked oats totalled 3.03 tons per hectare, diameter of hulled varieties amounted to 5.03 tons per hectare and other indicators also moved around the average values. It was confirmed that the newer varieties are breeding to a higher threshold of revenue, while old varieties exhibit better values of the quality parameters.
47

Fermentation, stability and degradability of whole-crop oat silage ensiled with a commercial inoculant

Pienaar, Johanni 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--Stellenbosch University, 2010. / ENGLISH ABSTRACT: South Africa is well-known for periodic dry periods and uncertain rainfall. Ensiling of crops is a method of preserving forage and ensures feed availability during periods when the supply of good quality forage is low. Cereal-based silages, especially in the Western Cape, South Africa, represent a significant proportion of feed consumed by ruminant animals, particularly high-producyion dairy cattle. However, farmers are still concerned about the technical challenges of ensiling cereal crops. Previous research done on lactic acid bacteria (LAB) inoculants used on cereal based silage has indicated a potential for improving silage fermentation, stability and degradability, thus enhancing feed conversion and production by ruminants. Two experiments were conducted to determine the effects of inoculating whole-crop oat silage with Lalsil® Cereal Lactobacilli (Lactobacillus buchneri (NCIMB 40788) and Pediococcus acidilactici (CNCM MA 18/5M)) LAB on (1) silage fermentation, (2) aerobic stability and (3) nutritional value of silage ensiled under a. micro-silos conditions and b. in a bunker under outdoor conditions of a Mediterranean summer. Oats (Avena sativa, cv SSH 405) were planted on 60 ha under dryland conditions at Elsenburg in the Western Cape province, South Africa. Whole-crop oats were harvested at the soft dough stage and length of the chopped material was 9 mm (Day of ensiling – Day 0). Chopped whole-crop oats were sampled, mixed thoroughly and divided into two portions. The Inoculant (Lalsil® Cereal) was applied to one portion to provide 5.79 x 109 colony forming units (CFU) of LAB per gram of fresh material. In the first experiment twenty - four glass silos (1.5 L glass jars) (WECK, GmbH u.Co., Wehr-Ofligen, W. Germany) were filled for each of the control and inoculant treatments. The glass silos were stored in a dark room in the laboratory at ambient temperature. Three glass silos were opened for each treatment on days 1, 2, 4, 8, 15, 30, 60 and 102 post-ensiling to determine fermentation dynamics. A parallel study was done with the same chopped whole-crop oats using the buried bag technique in a bunker silo. Whole-crop oats were ensiled in six net bags per treatment buried in a bunker filled with the same untreated whole crop oats. Bags, attached with nylon lines (3 m lengths) for easy retrieval were buried at 1m and 2 m depths in the same bunker. The net bags in the bunker were retrieved after 186 days of ensiling. Dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), crude protein (CP), lactic acid levels, pH, water soluble carbohydrates (WSC) and in vitro organic matter degradability (IVOMD) for both studies were determined. Silage of both experiments was exposed to aerobic conditions for ten days to determine aerobic stability. It is concluded that the inoculant Lalsil® Cereal had the effect of reducing the rate of consumption of WSC during the anaerobic phase and aerobic exposure for both experiments. Silage spoilage due to yeasts and moulds was however more evident with the inoculated silage due the presence of sugars in the micro-silos experiment. / AFRIKAANSE OPSOMMING: Suid-Afrika is bekend vir droë periodes en wisselvallige reënval. Die inkuiling van gewasse is ‘n goeie manier om ruvoer te voorsien in tye van droogtes of tekorte. Kleingraan kuilvoer is veral bekend in die Wes-Kaap, Suid-Afrika en maak ‘n groot deel uit van die melkkoei se rantsoen. Landbouers is nog steeds bekommerd oor die tegniese aspekte wanneer dit kom by die inkuil van gewasse. Vorige navorsing het getoon dat die gebruik van ‘n melksuurbakteriese inokulant saam met die inkuiling van gewasse moontlik die potensiaal het om fermentasie, stabiliteit en degradering te verbeter en sodoende voeromset te verbeter. Twee eksperimente is uitgevoer om die effek van die inkuiling van hawerkuilvoer met Lalsil® Cereal Lactobacilli (Lactobacillus buchneri (NCIMB 40788) en Pediococcus acidilactici (CNCM MA 18/5M)) LAB te bepaal op (1) kuilvoer fermentasie, (2) aërobiese stabiliteit en (3) nutriëntwaarde van die kuilvoer ingekuil in a. mikrosilo’s en b. in ‘n bunker in die buitelug. Hawer (Avena sativa, cv SSH 405) is op 60 ha droë land geplant op Elsenburg in die Wes-Kaap, Suid-Afrika. Die hawer is ingekuil tydens die sagte deeg stadium en die gekapte materiaal was ongeveer 9 mm lank. Gekapte material was deeglik gemeng en in twee gedeel. Die inokulant (Lalsil® Cereal) is op die een gedeelte gesproei om 5.79 x 109 kolonie-vormende eenhede (KVE) melksuurbakterieë per gram vars materiaal te voorsien. Tydens die eerste eksperiment is 24 mikrosilo’s (1.5 L glas silo) (WECK, GmbH u.Co., Wehr-Ofligen, W. Duitsland) vir elke behandeling vol kuilvoer gemaak. Hierdie mikrosilo’s is gestoor in ‘n donker kamer teen kamertemperatuur. Drie mikrosilo’s is per behandeling oopgemaak op dag 1, 4, 8, 15, 30, 60 en 102 na inkuiling om die fermentasie-dinamika te bepaal. ‘n Parallelle studie is gedoen met dieselfde materiaal ingekuil in netsakke binne die bunker. Die materiaal was ingekuil in ses netsakke vir elke behandeling. Nylon toue (3 m) is aan die sakke vasgemaak om die uithaal daarvan op latere stadium te vergemaklik. Hierdie sakke is ingekuil op verskillende dieptes, 1 m en 2 m in dieselfde bunker. Die sakke is na 186 dae weer uitgehaal. Droë materiaal (DM), organiese materiaal (OM), neutraal bestande vesel (NBV), ruproteïen (RP), melksuurvlakke, pH, water oplosbare koolhidrate (WOK) en in vitro organiese materiaal verteerbaarheid (IVOMV) vir beide studies is bepaal. Kuilvoer van beide eksperimente is ook blootgestel aan aërobiese toestande vir 10 dae aan aërobiese toestande blootgestel om aërobiese stabiliteit te bepaal. Daar is bepaal dat die inokulant Lalsil® Cereal het die tempo van WOK verbruik verminder gedurende die anaërobies fase sowel as die aërobiese fase vir beide eksperimente. Kuilvoer wat bederf het as gevolg van giste en swamme was meer sigbaar by die inokulant behandelde kuilvoer as gevolg van die teenwoordigheid van suikers in die mikrosilo’s. (Sleutelwoorde: hawerkuilvoer, inokulant, mikrosilo’s, water oplosbare koolhidrate (WOK), in vitro organiese materiaal verteerbaarheid (IVOMV))
48

Interaktion der Organische-Anionen-Transporter 1 und 3 mit Dicarboxylaten / Interactions of the organic anion transporters 1 and 3 with dicarboxylates

Kaufhold, Marcel 05 March 2013 (has links)
Organische Anionen werden aus dem Blut in die proximalen Tubuluszellen durch Organische-Anionen-Transporter 1 und 3 (OAT1 und OAT3) aufgenommen. Die Aufnahme erfolgt im Austausch gegen Dicarboxylate. In dieser Dissertation wurde die Affinität von Dicarboxylaten gegenüber humanen OAT1 und OAT3 untersucht mit dem Ziel mehr Informationen über die Struktur der Transporter zu erhalten. Es sollten Unterschiede zwischen dem OAT1 und OAT3 ermittelt werden, besonders bezüglich deren Substratspezifität. Alle Transporter wurden stabil in HEK293-Zellen exprimiert. Extrazellulär wurden Dicarboxylate als Inhibitoren gegen die 3H-p-Aminohippurat-Aufnahme (OAT1) oder 3H-Östronsulfat-Aufnahme (OAT3) zugefügt. OAT1 zeigt die höchste Affinität gegenüber Glutarat (IC50 3,3 µM), α-Ketoglutarat (IC50 4,7 µM) und Adipat (IC50 6,2 µM), gefolgt von Pimelat (IC50 18,6 µM) und Suberat (IC50 19,3 µM). Die Affinität von OAT1 gegenüber Succinat und Fumarat war gering. Der OAT3 zeigte dieselbe Dicarboxylat-Selektivität mit etwa 13-mal höheren IC50-Werten verglichen mit dem OAT1. Die Daten charakterisieren α-Ketoglutarat als hochaffines Substrat für den OAT1 und den OAT3. Die Ergebnisse deuten auf eine ähnliche Molekülstruktur der Bindungsstellen von OAT1 und OAT3 hin.
49

Funktionelle Charakterisierung des humanen Organische-Anionen-Transporters 4 (hOAT4) / Functional characterization of human renal organic anion transporter 4 (hOAT4)

Stein, Daniel 06 March 2018 (has links)
No description available.
50

Development of a Functional Shelf Stable High Protein Dairy Beverage with Oat-beta-glucan

Vasquez Orejarena, Eva G. 21 November 2016 (has links)
No description available.

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