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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.
1

Organinių azoto trąšų „Provita“ įtaka ekologiškai auginamų bulvių derlingumui, derliaus kokybei ir dirvožemio savybėms / The effect of organic nitric fertilizers Provita to the harvest, quality and soil properties of organically cultivated potatoes

Bičius, Žydrūnas 08 June 2009 (has links)
2008 m. Lietuvos žemės ūkio universiteto Bandymų stotyje atlikus organinių azoto trąšų Provita įtakos ekologiškai auginamoms bulvėms tyrimus, nustatyta, kad tręšimas organinėmis azoto trąšomis Provita, bei organinių azoto trąšų Provita deriniais su Patenkali ir fosforitmilčiais esminiai padidino bulvių suminį ir prekinį derlingumą bei derliaus prekingumą. Patręšus Provita, Patenkali ir fosforitmilčiais bei Provita ir Patenkali esminiai padidėjo suminis ir prekinis bulvių derlingumas, lyginant su tręšimu Provita bei Provita ir fosforitmilčių trąšų deriniu. Bulves patręšus Provita, Provita ir Patenkali bei Provita, Patenkali ir fosforitmilčiais esminiai sumažėjo bulvėse krakmolo, lyginant su netręštomis bulvėmis. Patręšus bulves organinėmis azoto trąšomis Provita esminiai sumažėjo sausųjų medžiagų bulvių gumbuose, lyginant su netręštomis bulvėmis bei tręšimu Provita, kalio ir fosforo trąšų deriniais. Tręšiant organinėmis azoto trąšomis Provita gautas neigiamas azoto balansas. Tręšimas N60 organinių azoto trąšų norma, neužtikrino teigiamo azoto balanso dirvožemyje. / Research on the effect of organic nitric fertilizers Provita to organically cultivated potatoes performed in 2008 at the experimental station of Lithuanian University of Agriculture highlighted, that fertilization of potatoes with organic nitric fertilizers Provita, as well as combinations of organic nitric fertilizers Provita with Patenkali and phosphorite powder, significantly increased total and marketable harvest of potatoes, as well as merchantability of harvest. In case of fertilization with Provita, Patenkali and phosphorite powder, as well as Provita and Patenkali, total and marketable harvest of potatoes was significantly increased, compared with fertilization using Provita and the combination of Provita and phosphorite powder. After fertilization of potatoes with Provita, Provita and Patenkali as well as Provita, Patenkali and phosphorite powder, the concentration of starch in potatoes was significanlty lower, than in these never fertilized. After fertilization of potatoes with organic nitric fertilizers Provita, the concentration of dry matterial in potatoes was significantly decreased, compared to these never fertilized, or fertilized with Provita, combinations of kalium and phosphoric fertilizers. Fertilization of potatoes had no significant effect to the concentration of soluble dry matterial in potatoes. Fertilization with organic nitric fertilizers Provita resulted in negative nitric balance. Fertilization with standard volume of organic nitric fertilizers N... [to full text]
2

Design of a Structure Search Engine for Chemical Compound Database

Wang, Hao 02 May 2008 (has links)
The search for structural fragments (substructures) of compounds is very important in medicinal chemistry, QSAR, spectroscopy, and many other fields. In the last decade, with the development of hardware and evolution of database technologies, more and more chemical compound database applications have been developed along with interfaces of searching for targets based on user input. Due to the algorithmic complexity of structure comparison, essentially a graph isomorphism problem, the current applications mainly work by the approximation of the comparison problem based on certain chemical perceptions and their search interfaces are often e-mail based. The procedure of approximation usually invokes subjective assumption. Therefore, the accuracy of the search is undermined, which may not be acceptable for researchers because in a time-consuming drug design, accuracy is always the first priority. In this dissertation, a design of a search engine for chemical compound database is presented.The design focuses on providing a solution to develop an accurate and fast search engine without sacrificing performance. The solution is comprehensive in a way that a series of related problems were addressed throughout the dissertation with proposed methods. Based on the design, a flexible computing model working for compound search engine can be established and the model can be easily applied to other applications as well. To verify the solution in a practical manner, an implementation based on the presented solution was developed. The implementation clarifies the coupling between theoretic design and technique development. In addition, a workable implementation can be deployed to test the efficiency and effectiveness of the design under variant of experimental data.
3

Características agronômicas, qualidade e composição química dos grãos de híbridos simples de milho doce

Kwiatkowski, Angela January 2007 (has links)
CNPQ / O milho doce (Zea mays L.) possui ampla versatilidade, além de agregar valor ao produto. Este tipo de milho vem sendo consumido em diversos países na forma de espiga cozida “in natura”, congelada ou como grãos enlatados. No Brasil, várias agroindústrias fomentam a produção e comercialização do milho doce enlatado em conserva. Dessa forma, seu cultivo vem crescendo gradativamente, atraindo a atenção dos produtores de milho verde. O presente trabalho possui como objetivos: avaliar caracteres agronômicos, a qualidade e a composição química dos grãos de híbridos simples de milho doce apropriados para consumo "in natura" e, também, pela indústria de milho verde em conserva. As sete linhagens foram selecionadas e fornecidas para o cruzamento dialélico pelo Programa de Melhoramento Genético da Universidade Estadual de Maringá, sendo obtidos os 21 híbridos simples. O delineamento experimental foi o de blocos completos casualizados com quatro repetições. As características avaliadas no campo foram: altura de plantas, altura de inserção das espigas e massa das espigas sem palha (kg ha-1). As avaliações químicas realizadas foram: determinação de açúcares redutores e totais, amido, proteínas, extrato etéreo, fibras e cinzas. Para as análises estatísticas, foi utilizada a análise de variância e na comparação das médias foi utilizado o teste de agrupamento Scott- Knott (1974) com probabilidade mínima de 5%. Para a análise de combinação entre as linhagens genitoras e os híbridos simples obtidos (capacidade geral de combinação – CGC - e capacidade específica de combinação - CEC) foi utilizado o método 4 de Griffing e o modelo fixo (1956). Os resultados médios obtidos indicam que, para a avaliação da altura de plantas e espigas, não houve diferença significativa x (P>0,05), e para a composição química, houve diferença significativa (P<0,05) pelo teste de agrupamento de médias de Scott-Knott (1974) entre os híbridos avaliados. Na análise combinatória, as linhagens de milho doce que se destacaram para os cruzamentos realizados foram as linhagens L4 e L5. Os híbridos L4xL5 e L3xL7 são os mais indicados para produção, quando se objetiva a maior concentração de açúcares e menor teor de amido na composição. / Sweet corn (Zea mays L.) possesses wide versatility, besides adding value to the product. This corn type has been consumed ‘in natura’ in several countries, in form of cooked ears, or in frozen or canned grains. In Brazil, several agribusinesses foment the production and commercialization of canned sweet corn. Thus, its cultivation has been growing gradually, attracting the attention of green corn producers. The present paper has as objective to evaluate the agronomic characters, the quality and the chemical composition of the grains of sweet corn, simple hybrids, appropriate for consumption ‘in natura’, and the corn to be used in the green corn industry. Seven lineages were selected and supplied for the dialectic crossing by the Program of Genetics Improvement of the State University of Maringá, thus obtaining 21 simple hybrids. The experimental outlining occurred by using complete randomized blocks with four replications. The characteristics appraised in the cultivars were: height of plants, height of ear insertion and mass of corn ears, without straw (kg ha-1). The chemical evaluations carried out were the ones regarding: determination of reducer and total sugars, starch, proteins, ethereal extract, fibers and ashes. Variance analysis was used for the statistical analyses, whereas Scott-Knott cluster test (1974) was used in the comparison of averages, with a minimum probability of 5%. For the combining analysis, between the genitor lineages and the simple hybrids obtained (usual combination capacity - UCC - and specific combination capacity - SCC), both, method 4 and the fixed model by Griffing (1956) were used. The average results obtained showed that there was no significant difference when the evaluating the height of plants and corns ears (P>0.05), but on xii the other hand, of chemical composition showed significant difference (P<0.05) in the test regarding average clustering, by Scott-Knott (1974) for the hybrids appraised. But L4 and L5 sweet corn lineages were the ones highlighted for the crossings accomplished in the combining analysis. Both, L4xL5 and L3xL7 hybrids were the most suitable for production, when aiming at obtaining the largest concentration of sugars, together with the smallest content of starch, in its compound.
4

Características agronômicas, qualidade e composição química dos grãos de híbridos simples de milho doce

Kwiatkowski, Angela January 2007 (has links)
CNPQ / O milho doce (Zea mays L.) possui ampla versatilidade, além de agregar valor ao produto. Este tipo de milho vem sendo consumido em diversos países na forma de espiga cozida “in natura”, congelada ou como grãos enlatados. No Brasil, várias agroindústrias fomentam a produção e comercialização do milho doce enlatado em conserva. Dessa forma, seu cultivo vem crescendo gradativamente, atraindo a atenção dos produtores de milho verde. O presente trabalho possui como objetivos: avaliar caracteres agronômicos, a qualidade e a composição química dos grãos de híbridos simples de milho doce apropriados para consumo "in natura" e, também, pela indústria de milho verde em conserva. As sete linhagens foram selecionadas e fornecidas para o cruzamento dialélico pelo Programa de Melhoramento Genético da Universidade Estadual de Maringá, sendo obtidos os 21 híbridos simples. O delineamento experimental foi o de blocos completos casualizados com quatro repetições. As características avaliadas no campo foram: altura de plantas, altura de inserção das espigas e massa das espigas sem palha (kg ha-1). As avaliações químicas realizadas foram: determinação de açúcares redutores e totais, amido, proteínas, extrato etéreo, fibras e cinzas. Para as análises estatísticas, foi utilizada a análise de variância e na comparação das médias foi utilizado o teste de agrupamento Scott- Knott (1974) com probabilidade mínima de 5%. Para a análise de combinação entre as linhagens genitoras e os híbridos simples obtidos (capacidade geral de combinação – CGC - e capacidade específica de combinação - CEC) foi utilizado o método 4 de Griffing e o modelo fixo (1956). Os resultados médios obtidos indicam que, para a avaliação da altura de plantas e espigas, não houve diferença significativa x (P>0,05), e para a composição química, houve diferença significativa (P<0,05) pelo teste de agrupamento de médias de Scott-Knott (1974) entre os híbridos avaliados. Na análise combinatória, as linhagens de milho doce que se destacaram para os cruzamentos realizados foram as linhagens L4 e L5. Os híbridos L4xL5 e L3xL7 são os mais indicados para produção, quando se objetiva a maior concentração de açúcares e menor teor de amido na composição. / Sweet corn (Zea mays L.) possesses wide versatility, besides adding value to the product. This corn type has been consumed ‘in natura’ in several countries, in form of cooked ears, or in frozen or canned grains. In Brazil, several agribusinesses foment the production and commercialization of canned sweet corn. Thus, its cultivation has been growing gradually, attracting the attention of green corn producers. The present paper has as objective to evaluate the agronomic characters, the quality and the chemical composition of the grains of sweet corn, simple hybrids, appropriate for consumption ‘in natura’, and the corn to be used in the green corn industry. Seven lineages were selected and supplied for the dialectic crossing by the Program of Genetics Improvement of the State University of Maringá, thus obtaining 21 simple hybrids. The experimental outlining occurred by using complete randomized blocks with four replications. The characteristics appraised in the cultivars were: height of plants, height of ear insertion and mass of corn ears, without straw (kg ha-1). The chemical evaluations carried out were the ones regarding: determination of reducer and total sugars, starch, proteins, ethereal extract, fibers and ashes. Variance analysis was used for the statistical analyses, whereas Scott-Knott cluster test (1974) was used in the comparison of averages, with a minimum probability of 5%. For the combining analysis, between the genitor lineages and the simple hybrids obtained (usual combination capacity - UCC - and specific combination capacity - SCC), both, method 4 and the fixed model by Griffing (1956) were used. The average results obtained showed that there was no significant difference when the evaluating the height of plants and corns ears (P>0.05), but on xii the other hand, of chemical composition showed significant difference (P<0.05) in the test regarding average clustering, by Scott-Knott (1974) for the hybrids appraised. But L4 and L5 sweet corn lineages were the ones highlighted for the crossings accomplished in the combining analysis. Both, L4xL5 and L3xL7 hybrids were the most suitable for production, when aiming at obtaining the largest concentration of sugars, together with the smallest content of starch, in its compound.
5

Vliv různého hospodaření na produkci, strukturu a chemické složení nadzemní biomasy v povodí Mlýnského potoka / Effect of different management on the production, structure and chemical composition of abovegroung biomass in the Mlýnský potok catchment.

TRUHLÁŘ, Martin January 2015 (has links)
The aim of the thesis is to assess the changes in production and structure of surface biomass (the proportion of grasses, clovers and other plants) and its chemical compound in scythed and pastured grass areas in the monitored areas in the Mlýnský potok basin in years 2012 and 2014. The area is situated on the right bank of Lipno dam in Pasečná land register, 784 820 meters above sea-level. There were established three permanent sampling points in the pastured as well as scythed areas in the Mlýnský potok basin. Four samples of biomass from the area of 1 sq m were collected in each of these sampling points. These were collected on 20th June 2012, 11th September 2012, 17th June 2014 and 10th September 2014. The collected biomass was then divided into agro-botanical groups (grasses, clovers and other plants) and afterwards it was dried and weighed. The chemical analysis was conducted by a certified laboratory AGRO-LA, Ltd. in Jindřichův Hradec. The aim of the analysis was to find out the amount of nitrogen, phosphorus, potassium, magnesium and calcium. By assessing the development of the overall production of the biomass in 2012 and 2014 in the sampling area we found out a considerable decline of biomass in scythed areas and an increasing difference in the average amount of biomass between scythed and pastured areas during the monitored period. These findings were assessed as statistically conclusive. By assessing the development of overall proportions of the agro-botanical groups we could see a substantial decrease in grasses and on the other hand an increase of clovers and other plants in scythed areas compared to pastured areas. The difference between the proportion of grasses and other plants proved to be statistically conclusive. By assessing the development in difference of the overall average amount of nitrogen in the biomass, there emerged a considerable increase in the amount of nitrogen regardless the way of management. As far as phosphorus is concerned, we found out a decreasing difference in its amount between scythed and pastured areas. The amount of potassium was considerably lower in scythed areas, whereas calcium showed the exact opposite. Statistically conclusive were the findings of substantial increase of nitrogen in the surface biomass and also the changes in the amount of potassium and calcium due to the management. By evaluating these outcomes we confirmed that the permanent grass areas have a very variable productive and structural potential which holds true also for their chemical compound.
6

Analysis of Measurement of Analytes level in Girls age 6-9 year old

Dikong, Gabriel N. 04 August 2011 (has links)
No description available.
7

Diagnóstico e recuperação de solos afetados por sais em perímetro irrigado do sertão de Pernambuco / Diagnosis and recovery of soils affected by salts in irrigated perimeter of sertão in Pernambuco.

MIRANDA, Márcio Fléquisson Alves 20 February 2013 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-08-17T12:15:41Z No. of bitstreams: 1 Marcio Flequisson Alves Miranda.pdf: 1217281 bytes, checksum: bd45c2f7f20927f1da595dfd05965a6a (MD5) / Made available in DSpace on 2016-08-17T12:15:42Z (GMT). No. of bitstreams: 1 Marcio Flequisson Alves Miranda.pdf: 1217281 bytes, checksum: bd45c2f7f20927f1da595dfd05965a6a (MD5) Previous issue date: 2013-02-20 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In Northeastern Brazil, in recent decades, with the increase of irrigation using in irrigated perimeters, often with inadequate management to local conditions, the soil salinization and sodification processes have intensified, promoting degradation and abandonment of large areas previously productive. Thus, we carried out a field survey to investigate the soil degradation in irrigated perimeter situated in the municipality of Custodia, semiarid region in Pernambuco, Brazil. Firstly were identified areas with degraded soils by salts excess, and also was done the experiment assembly with the intent to recover those areas through the application of organic and chemicals compounds, besides the technique of phytoremediation with Atriplex nummularia. For that, soil samples were taken in all 55 plots that make up the perimeter in the 0-10, 10-30 and 30-60 cm layers for the soils physical and chemical characterization, and chemical analyzes of the water used on the perimeter during periods of July/2009, January/2010, July/2010 and January/2011. After the selection of the degraded area into the irrigated perimeter, was mounted an experiment to recover the degraded soil by the evaluation of the treatments: 1) planting of Atriplex nummularia Lindl, 2) application of bovine manure, 3) sheep manure, 4) polymer, 5) gypsum and 6) control (witness). Four samples were taken, the first being at the same time of the experiment assembly (October 2009). After that, three more samples were taken, at six (April 2010), twelve (October 2010) and eighteen months (April 2011) after experiment assembly. Soil samples were collected at 0-10, 10-30 and 30-60 cm depth for the chemical analyzes. To evaluate the physical properties, soil samples were collected in the first (October 2009) and in the last (April 2011) collection at 0-10 and 10-30 cm layers. Were monitored the soil attributes in relation to treatment application with respect to time. The soils of the irrigated perimeter from Custódia are in the process of degradation and need to have their properties monitored over time to prevent its development. Among the cations evaluated, soluble and exchangeable Na+ was what was in higher concentrations, followed by the Cl- and by the RAS variable, besides increasing the PST in depth. The phytoremediation technique was effective in improving the soils quality and the application of sheep manure and polyacrylamide based polymer also acted positively in improving the quality of soil chemistry and physics. / Na Região Nordeste do Brasil, nas últimas décadas, com o incremento da irrigação em perímetros irrigados, muitas vezes com manejo inadequado às condições locais, os processos de salinização e sodificação de solos têm se intensificado, promovendo a degradação e abandono de extensas áreas anteriormente produtivas. Assim, realizou-se o levantamento da situação de degradação do Perímetro Irrigado de Custódia, no Sertão de Pernambuco, onde foram identificadas áreas com problemas de excesso de sais, seguindo-se de montagem de experimento para recuperação de uma dessas áreas, através da aplicação de compostos orgânicos e químicos, além da técnica da fitorremediação com Atriplex nummularia. Para isso, foram realizadas amostragens de solos em todos os 55 lotes que compõem o perímetro nas profundidades de 0-10, 10-30 e 30-60 cm para a caracterização física e química dos solos, além das análises químicas das águas utilizadas no perímetro nos períodos de Julho/2009, Janeiro/2010, Julho/2010 e Janeiro/2011. Após seleção de área degradada do perímetro, foi montado experimento de recuperação do solo testando-se os tratamentos: 1) plantio de Atriplex nummularia Lindl, 2) aplicação de esterco bovino, 3) esterco ovino, 4) polímero, 5) gesso e 6) controle (testemunha). Foram realizadas quatro amostragens, sendo a primeira no momento da montagem do experimento (Outubro de 2009), aos seis (Abril de 2010), aos doze (Outubro de 2010) e aos dezoito meses (Abril de 2011). As amostras de solo foram coletadas nas camadas de 0-10, 10-30 e 30-60 cm de profundidade para realização das análises químicas. Para a realização das análises físicas do solo coletaram-se amostras de solo na primeira coleta (Outubro de 2009) e na ultima (Abril de 2011) nas profundidades de 0-10 cm e 10-30 cm. Foram monitorados os atributos do solo com a aplicação dos tratamentos em função do tempo. Os solos do Perímetro Irrigado de Custódia encontram-se em processo de degradação e precisam ter suas propriedades monitoradas ao longo do tempo para evitar sua evolução. Entre os cátions avaliados, o Na+ solúvel e trocável foi o que esteve em concentrações mais elevadas, seguido pelo Cl- e pela variável RAS, além do aumento da PST em profundidade. A técnica da fitorremediação foi efetiva na melhoria da qualidade dos solos estudados e a aplicação do esterco ovino e do polímero a base de poliacrilamida também atuaram positivamente na melhoria da qualidade química e física do solo.
8

Phytochemical evaluation of Curtisia dentata (Burm.f.) C.A.Sm. stem bark and seasonal and geographical region variability

Van Wyk, Anna Susanna 08 1900 (has links)
The stem bark of the protected tree species, Curtisia dentata (Burm. f.)C.A.Sm., is one of the most popular plant species harvested and traded at traditional medicine markets in South Africa. The overexploitation of C. dentata trees lead to a “Near Threatened” conservation status and the population trend is portrayed as “declining”. In the KwaZulu-Natal Province of South Africa, C. dentata is completely conservation dependent. This study is not based on drug discovery or toxicological studies, but on the concern that the stem bark of C. dentata trees are harvested, prepared into remedies and consumed as traditional medicine without knowledge regarding the chemical compounds in the stem bark, particularly since the chemical composition of C. dentata stem bark was unknown to date. Phytochemical analyses were firstly conducted to determine the chemical composition of C. dentata stem bark using various solvents and various analytical methods, and secondly, to determine how seasons and regional separation of C. dentata trees affect the chemical profiles of C. dentata stem bark from an environmental and nature conservation perspective. Plants are known to contain numerous chemical compounds. Compounds isolated from a particular plant species are therefore not the only compounds present in that species, and although a plant has proven pharmacological properties, they can still cause harm. Previous studies on C. dentata aimed at validating the plant species as a medicinal plant by examining extracts of the leaves, twigs and stem bark’s potentials against known pathogens and selected cancer cells in vitro and in vivo, and its anti-inflammatory, antioxidant and antiverotoxic properties. Four pentacyclic triterpenoids and one steroidal compound were also previously isolated from C. dentata leaves, however, the leaves are not used in traditional medicines, but were suggested as alternative for stem bark as the harvesting of leaves is less destructive. The efficacy of these compounds as therapeutic agents is, however, compromised by their low solubility in water and thus their potential to penetrate permeating biological membranes. Moreover, in vitro toxicity studies distort the picture of its actual potentials on human health as the whole human metabolome and all its processes, including uptake and phase I and phase II biotransformation are not included. In vivo toxicity studies on mammalian animal species may also not present a true picture of a chemical or extract’s toxic effects on humans as animal metabolisms differ from those of humans. The chemical composition of leaves and stem bark may furthermore also be in contrast to some extent, and therefore chemical compounds were also isolated from C. dentata stem bark in this study. Scientific studies on plant-based medicines generally involve the discovery or identification of compounds that may be beneficial, and which can be exploited in future. Chemical compounds in traditional medicines or other plant-based health products which may cause adverse effects are generally ignored. Moreover, scientific studies that consider that some compounds present in plant extracts may derive from contaminants are equally limited. Traditional plant-based medicines are neither standardized nor regulated in South Africa. Users of traditional plant-based traditional medicines therefore consume uncertain dosages of both beneficial and hazardous substances, as well as contaminants simultaneously. Certain chemical compounds are carcinogens or mutagens or have the ability to accumulate in human tissues. Adverse effects may therefore only manifest after several years of use and will subsequently not be connected to the use of a particular traditional plant-based medicine. The goal of the thesis is therefore to provide a holistic portrayal of the full spectrum of chemical compounds in extracts of C. dentata stem bark and to discuss, where literature is available, the effect(s) each chemical compound may have on human health. Moreover, this thesis investigates variations in chemical composition and concentration in individual trees, seasonal variations and variations in composition and concentrations in the stem bark of C. dentata trees from geographically distinct regions. Most unexpected was that not all C. dentata stem bark samples contained chemical compounds with known beneficial potentials at each sampling date, and that chemical compounds may be region-specific and also tree-specific, which confirms that plants produce secondary metabolites according to the needs of each individual plant. Additional insight into the chemical composition and concentration of C. dentata trees is provided by the distribution profiles of amino acids in C. dentata stem bark. Extreme variations within populations and between geographical areas support the need for the cultivation of C. dentata trees to ensure sustainable production of homogenous material for chemical homogeneity. / Environment Science / PhD. (Environment Science)

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