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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.
51

Agricultural Trade Performance and Potential: A Retrospective Panel Data Analysis of US Exports of Corn and Soybeans

Grossen, Grace Elizabeth 22 August 2019 (has links)
There are a variety of international issues that disrupt the global trade market, an important one being national policies on the regulation of genetically modified organisms, or GMOs. Many crops have been genetically modified for reasons from herbicide resistance to correcting dietary shortfalls. This study evaluates the United States' exports of corn and soybeans from 1998 to 2016 to identify unusual shocks in trade values. In particular, this study quantifies how the importers' policy stance on the GMO issue impacts bilateral trade values. I estimate a gravity model with both ordinary least squares (OLS) and Poisson pseudo maximum likelihood (PPML) estimations. Residual analysis is used to assess the difference between actual trade and the trade levels predicted by the models. The results suggest that anti-GMO policies reduce trade values by an average of 11%. The largest difference between predictions and actual trade values is seen in corn exports to the European Union. Between 1998 and 2016, this forgone trade in corn was valued at $52.7 billion, which is $2.77 billion per year on average. This value is similar to the annual average value of U.S. exports of corn to Japan in the same period, $2.46 billion. The results have important implications for the agricultural industry. For developing nations, adoption of GMO crops could increase productivity and help alleviate poverty. Ultimately, the decision to adopt is up to the consumer, so the factors of consumer knowledge and opinions of GMOs are not to be ignored. / Master of Science / There are a variety of international issues that disrupt the global trade market, an important one being national policies on the regulation of genetically modified organisms, or GMOs. This study evaluates the United States’ exports of corn and soybeans from 1998 to 2016 to identify unusual drops in trade values. In particular, this study quantifies how the importers’ policy stance on the GMO issue impacts bilateral trade values. I estimate a gravity model with various estimation methods. Residual analysis is used to assess the difference between actual trade and the trade levels predicted by the models. The results suggest that anti-GMO policies reduce trade values by an average of 11%. The largest difference between predictions and actual trade values is seen in corn exports to the European Union. Between 1998 and 2016, this forgone trade in corn was valued at $52.7 billion, which is $2.77 billion per year on average. This value is similar to the annual average value of U.S. exports of corn to Japan in the same period, $2.46 billion. The results have important implications for the agricultural industry. For developing nations, adoption of GMO crops could increase productivity and help alleviate poverty. Ultimately, the decision to adopt is up to the consumer, so the factors of consumer knowledge and opinions of GMOs are not to be ignored.
52

Hypolipidemic, antioxidative and vascular effects of soy leaves (Glycine max L. Merr.).

January 2001 (has links)
Ho Hing Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 140-156). / Abstracts in English and Chinese. / Chapter Chapter 1 --- General introduction / Chapter 1.1 --- History of soybean --- p.1 / Chapter 1.2 --- Health benefits of soybean --- p.2 / Chapter 1.3 --- Introduction to flavonoids --- p.2 / Chapter 1.4 --- Bioavailability of flavonoids from foods --- p.3 / Chapter 1.5 --- Pharmacological effects of flavonoids and their glycosides --- p.4 / Chapter 1.5.1 --- Anticarcinogenic activity --- p.4 / Chapter 1.5.2 --- Antioxidative activity --- p.7 / Chapter 1.5.3 --- Cardioprotective activity --- p.9 / Chapter 1.5.4 --- Osteoprotective activity --- p.10 / Chapter 1.5.5 --- Neuroprotective activity --- p.12 / Chapter 1.5.6 --- Antiangiogenic activity --- p.12 / Chapter 1.6 --- Soy leaves --- p.13 / Chapter Chapter 2 --- Isolation and purification of kaempferol glycosides and genistin in soy leaves / Chapter 2.1 --- Introduction --- p.14 / Chapter 2.2 --- Objectives --- p.15 / Chapter 2.3 --- Materials and Methods --- p.16 / Chapter 2.3.1 --- Extraction and isolation --- p.16 / Chapter 2.3.1.1 --- Preparation of soy leaves butanol extract --- p.16 / Chapter 2.3.1.2 --- Preparation of kaempferol glycosides from soy leaves butanol extract --- p.16 / Chapter 2.3.2 --- High performance liquid chromatography (HPLC) analysis --- p.19 / Chapter 2.3.2.1 --- Sample preparation for the HPLC analysis --- p.19 / Chapter 2.3.2.2 --- HPLC analysis --- p.19 / Chapter 2.3.2.3 --- Quantification of the flavonoids and their glycosides --- p.23 / Chapter 2.3.2.4 --- Change in flavonoids and their glycosides in soy leaves --- p.23 / Chapter 2.4 --- Results --- p.24 / Chapter 2.4.1 --- Compound 1 --- p.24 / Chapter 2.4.2 --- Compound 2 --- p.24 / Chapter 2.4.3 --- Compound 3 --- p.25 / Chapter 2.4.4 --- Compound 4 --- p.25 / Chapter 2.4.5 --- Compound 5 --- p.25 / Chapter 2.4.6 --- Compound 6 --- p.26 / Chapter 2.4.7 --- Quantification of flavonoids in soybean and soy leaves --- p.32 / Chapter 2.4.8 --- Age-dependent changes in flavonoids and their glycosides --- p.32 / Chapter 2.5 --- Discussion --- p.35 / Chapter 2.5.1 --- Compound 1 --- p.35 / Chapter 2.5.2 --- Compound 2 --- p.35 / Chapter 2.5.3 --- Compound 3 --- p.37 / Chapter 2.5.4 --- Compound 4 --- p.38 / Chapter 2.5.5 --- Compound 5 --- p.39 / Chapter 2.5.6 --- Compound 6 --- p.40 / Chapter 2.5.7 --- Age-dependent changes in flavonoids and their glycosides --- p.40 / Chapter Chapter 3 --- Hypolipidemic effects of soy leaves in hamsters / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.1.1 --- Different lipoproteins and their functions --- p.41 / Chapter 3.1.2 --- Risk factors of cardiovascular disease --- p.42 / Chapter 3.1.3 --- Animal model --- p.43 / Chapter 3.2 --- Objectives --- p.44 / Chapter 3.3 --- Materials and Methods --- p.45 / Chapter 3.3.1 --- Animals --- p.46 / Chapter 3.3.2 --- Serum lipid and lipoprotein determinations --- p.46 / Chapter 3.3.3 --- Determination of cholesterol in the liver and adipose tissue --- p.46 / Chapter 3.3.4 --- Extraction of neutral and acidic sterols from fecal samples --- p.49 / Chapter 3.3.4.1 --- Determination of neutral sterols --- p.49 / Chapter 3.3.4.2 --- Determination of acidic sterols --- p.50 / Chapter 3.3.4.3 --- GLC analysis of neutral and acidic sterols --- p.51 / Chapter 3.3.5 --- Statistics --- p.51 / Chapter 3.4 --- Results --- p.54 / Chapter 3.4.1 --- Growth and food intake --- p.54 / Chapter 3.4.2 --- "Effects of SLP and SLEE supplementation on serum triacylglycerol (TG), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C)" --- p.54 / Chapter 3.4.3 --- Effects ofSLP and SLEE supplementation on non-HDL-C and ratio of non-HDL-C to HDL-C --- p.55 / Chapter 3.4.4 --- Effects of SLP amd SLEE supplementations on concentration of hepatic cholesterol --- p.58 / Chapter 3.4.5 --- Effects of SLP and SLEE supplementations on perirenal adipose tissue cholesterol --- p.58 / Chapter 3.4.6 --- Effects of SLP and SLEE supplementations on fecal neutral and acidic sterols --- p.61 / Chapter 3.5 --- Discussion --- p.64 / Chapter Chapter 4 --- Effects of soy leaves and its flavonoid glycosides on haemolysis and on LDL oxidation / Chapter 4.1 --- Introduction --- p.67 / Chapter 4.1.1 --- Role of low density lipoprotein oxidation in the development of atherosclerosis --- p.68 / Chapter 4.1.2 --- LDL oxidation --- p.70 / Chapter 4.1.3 --- Thiobarbituric acid reactive substances (TBARS) as an index of LDL oxidation --- p.71 / Chapter 4.1.4 --- Antioxidant and LDL oxidation --- p.74 / Chapter 4.2 --- Objective --- p.75 / Chapter 4.3 --- Materials and methods --- p.76 / Chapter 4.3.1 --- Isolation of LDL from human serum --- p.76 / Chapter 4.3.2 --- LDL oxidation --- p.77 / Chapter 4.3.3 --- Determine the formation of thiobarbituric acid-reactive substances (TBARS) --- p.77 / Chapter 4.3.4 --- Assay for erythrocyte haemolysis --- p.78 / Chapter 4.3.5 --- Statistics --- p.79 / Chapter 4.4 --- Results --- p.80 / Chapter 4.4.1 --- Effects of three different soy leaves extracts and flavonoid glycosides on LDL oxidation --- p.80 / Chapter 4.4.2 --- Effects of three soy leaves extracts and flavonoid glycosides on erythrocyte haemolysis --- p.80 / Chapter 4.5 --- Discussion --- p.85 / Chapter Chapter 5 --- Relaxing effects of soy leaves and its flavonoids / Chapter 5.1 --- Introduction --- p.89 / Chapter 5.1.1 --- Smooth muscle contraction --- p.90 / Chapter 5.1.1.1 --- Sliding filament mechanism --- p.91 / Chapter 5.1.2 --- Intracellular mechanisms involved in the regulation of smooth muscle contraction --- p.92 / Chapter 5.1.2.1 --- Voltage-gated Ca2+ channels --- p.92 / Chapter 5.1.2.2 --- Protein kinase C (PKC) mediated smooth muscle contraction --- p.93 / Chapter 5.1.2.3 --- Thromboxane A2 receptor-mediated calcium channel --- p.94 / Chapter 5.2 --- Objectives --- p.96 / Chapter 5.3 --- Materials and methods --- p.97 / Chapter 5.3.1 --- Drugs preparation --- p.97 / Chapter 5.3.2 --- Vessel preparation --- p.97 / Chapter 5.3.3 --- Contraction experiments --- p.99 / Chapter 5.3.3.1 --- Relaxant responses of soy leaves butanol extract on the contraction induced by different constrictors --- p.99 / Chapter 5.3.3.2 --- Relaxant responses of soy leaves butanol extract on U46619 and PGF2a- induced contraction --- p.99 / Chapter 5.3.3.3 --- "Relaxant responses of genistein, genistin and the kaempferol glycosides on U46619-induced contraction" --- p.100 / Chapter 5.3.4 --- Statistics --- p.100 / Chapter 5.4 --- Results --- p.102 / Chapter 5.4.1 --- Effect of soy leaves butanol extract --- p.102 / Chapter 5.4.2 --- Role of endothelium in extract-induced relaxation --- p.102 / Chapter 5.4.3 --- Effect of the soy leaves butanol extract on contractile response to prostaglandins --- p.103 / Chapter 5.4.4 --- Effects of kaempferol glycosides and kaempferol --- p.111 / Chapter 5.4.5 --- Effects of genistein and genistin --- p.111 / Chapter 5.5 --- Discussion --- p.118 / Chapter Chapter 6 --- Effect of soy leaves on mammary tumor / Chapter 6.1 --- Introduction --- p.123 / Chapter 6.1.1 --- Carcinogenesis --- p.123 / Chapter 6.1.1.1 --- In itiation --- p.124 / Chapter 6.1.1.2 --- Promotion --- p.124 / Chapter 6.1.1.3 --- Progression --- p.125 / Chapter 6.2 --- Objective --- p.126 / Chapter 6.3 --- Materials and methods --- p.127 / Chapter 6.3.1 --- Animal --- p.127 / Chapter 6.3.2 --- Determination of estrus cycle --- p.128 / Chapter 6.3.3 --- Statistics --- p.129 / Chapter 6.4 --- Results --- p.131 / Chapter 6.4.1 --- Incident rate of tumor induction --- p.131 / Chapter 6.4.2 --- Number of tumor induced --- p.131 / Chapter 6.5 --- Discussion --- p.136 / Chapter Chapter 7 --- Conclusions --- p.136 / References --- p.140
53

Systematic optimization of yield-enhancing applications in soybeans

Haverkamp, Bryson January 1900 (has links)
Master of Science / Department of Agronomy / Kraig Roozeboom / High soybean [Glycine max.] commodity prices in recent years have led to an increase in use of yield enhancing and protecting products. These products need to be evaluated to determine if the use of multiple inputs has a positive impact on yield and how these inputs interact with agronomic practices. The objectives of this study were to evaluate products individually and collectively in input systems, examine interactions between varieties and input systems (IS), seeding rates (SR) and IS, and row spacing (RS) and IS. Field experiments were conducted at high-yielding locations in Kansas and Minnesota in 2012 to 2014 to meet these objectives. Sixteen treatments consisting of individual inputs and inputs combined in systems were evaluated in one experiment. A second experiment evaluated the variety by IS interaction by constructing 18 treatments from a factorial combination of six glyphosate [N-(phosphonomethyl) glycine] resistant varieties and three IS’s: untreated control (UTC), SOYA (combination of possible yield-enhancing products representative of those currently being marketed), and SOYA minus foliar fungicide (SOYA – foliar F). A third experiment evaluated the SR by IS interaction by constructing 12 treatments from a factorial arrangement of six SR’s and two IS’s: UTC and SOYA. A fourth experiment evaluated the RS by IS interaction by constructing 12 treatments from a factorial arrangement of three RS’s and four IS’s: UTC, fungicide and insecticide seed treatment plus foliar fungicide (STFF), SOYA, and SOYA – foliar F. Very few interactions between IS and agronomic practices were detected in any of the experiments. Varieties had an effect on multiple growth parameters but yield differences were marginal; linear-plateau and non-linear models found that seeding rates that maximized yield in this study were similar to University recommendations; and in general, narrow rows produced the greatest yields. The use of inputs and IS’s typically increased seed mass and yield above the UTC across all experiments. However, given current costs and soybean prices, yield response to IS’s was not great enough to cover the additional costs. Overall, it appears producers would be better served by focusing on agronomic practices rather than implementing input systems.
54

Impacts and correction of potassium deficiency in no-till and strip-till soybean and corn production

Blocker, Shannon M. January 1900 (has links)
Master of Science / Department of Agronomy / David B. Mengel / This study was initiated to determine if potassium (K) deficiencies seen in soybeans (Glycine max (L.) Merr.) under no-till and strip-till production systems are impacting soybean yields, and if so, what fertilizer application practices including: rate of K application; broadcast or deep band methods of application; and the use of starter fertilizer at planting; could be used to correct the problem. The residual impacts of K fertilization and placement were also evaluated on corn (Zea mays L.) grown in rotation with soybeans. This research was conducted on-farm in cooperation with local producers. Soybeans sites in 2007 were near Harris, Ottawa and Westphalia, Kansas with corn planted in 2008 at the sites near Ottawa and Westphalia. Soybean sites in 2008 were located near Ottawa and Welda, Kansas. Selected sites were generally near or below the current soil test K critical level of 130 mg per kg extractable K, based on sampling histories provided by the cooperators. Sampling in the spring of 2007 confirmed these soil test (ST) K levels. Soybean leaf tissue potassium levels in 2007 were less than the critical level of 17 mg per kg in the unfertilized control plots, and were significantly greater when potassium fertilizer was deep banded or a high-rate of K fertilizer was broadcast. No significant difference in yield of soybeans due to K fertilization was seen, likely due to significant water stress during the grain fill period, which severely limited soybean yield in 2007. Soil test K levels at all the research sites increased dramatically between 2007 and 2008, even where no K was applied. Different weather conditions experienced these two years may have contributed to this occurrence. No residual impacts of K fertilization in 2007 on soybeans were seen in soil tests, corn leaf tissue K levels or corn yield in 2008. Soybean sites in 2008 also showed a dramatic increase in K ST levels in 2008 as compared to farmer records. No effects of K fertilization on soybean growth or yield were seen in 2008. The 2008 Ottawa soybean site had very low P soil tests. A significant response to P fertilization contained in the starter treatments was observed. This suggests that the dominant farmer practice of applying P and K fertilizer to corn, and not applying fertilizer directly to soybeans, even at low soil test levels, may not be supplying adequate P to soybeans, and is likely costing farmers yields and profits.
55

Studies on I) Dry Matter and Nitrogen Disappearance of Six Soybean Protein Products In Situ and II) Contamination of In Situ Dry Matter and Nitrogen Disappearance with Acid Detergent Fiber

Coomer, James 01 July 1989 (has links)
In experiment I), dry matter disappearance (DMD) and nitrogen disappearance (ND) of raw soybeans (RAW), solvent extracted soybean meal (SBM), heat treated whole soybeans (HT), mechanically extracted soybean meal (MEX), dry extruded soybeans (DEX), and wet extruded soybeans (TEX), were studied in situ for times of 3, 6, 12 and 24 h of rumen exposure. Five gram, air dry, samples were suspended in the rumen of a lactating Holstein cow fed a total mixed ration twice daily. The percent DMD for 24 h was as follows: RAW-85.9; SBM-56.6; HT-39.0; MEX-40.2; DEX-28.0; TEX-43.3. The greatest DMD was observed with RAW and was greater than all others (P<.01), followed by SBM which was significantly greater than all but Raw (P<.01). DEX presented the lowest DMD when compared to all other (P<.01). Percent ND values for 24 h for the soy products were: RAW-90.8; SBM-47.0; HT-32.7; MEX-23.7; DEX-16.5; TEX-23.0. The ND for RAW was significantly greater (P<.01) than all others, while the ND for SBM was similar P>.01) to HT but greater (P<.01) than MEX, DEX and TEX. ND for HT, MEX, DEX and TEX were similar (P>.01). Significant differences were observed in DMD and ND of various soybean products. As expected a high degree of degradation and ND was observed with raw soybeans. The application of heat decreased DMD and ND in SBM and application of greater heat (HT, MEX and DEX) and application of heat with moisture (TEX) resulted in products with lower DMD and lower ND. In experiment II) wheat straw acid detergent fiber (ADF) was subjected to in situ DMD and ND studies. Effects of time (612-24 h) and sample weight (1-2-3 grams) were evaluated. A lactating Holstein cow being fed a mixed ration was used. ADF dry matter (DM) weights (after incubation) expressed as a % of the original sample, were as follows: one gram: 101, 110 and 136; two grams: 99, 106 and 110; and three grams: 97, 110 and 114 for 6, 12 and 24 h respectively. The ADF DM weights of the one and two gram samples were significantly higher (P<.05) for 12 and 24 h than 6 h. When sample sizes were combined for each time, comparisons found 24 h to be significantly higher (P<.01) than 6 h. The DM changes were also reflected and magnified in the % N changes in the ADF residues. The amount of N of the one gram ADF samples increased 32% after 6 h, 122% after 12 h and 287% after 24 h (24>12>6-P<.01), and for two grams 29%-6 h, 97%-12 h and 117%-24 h (24>12>6-P<.05), and for three grams 34%-6 h, 140%-12 h and 142%-24 h (24 and 12>6-P<.01). Potential problems with DM and N contamination of ADF residue with in situ studies were demonstrated with small increases in DM weights and larger increases in N content.
56

Effect of Lygus bugs (Hemiptera: Miridae) on field beans in Manitoba

NAGALINGAM, THARSHINIDEVY 04 1900 (has links)
Lygus lineolaris (Palisot de Beauvois), L. elisus (Van Duzee), L. borealis (Knight) and Adelphocoris lineolatus (Goeze) were the major species of plant bugs present in commercial field bean and soybean fields in 2008–2010. Lygus lineolaris comprised 78–95% of the mirid adults and <10% were A. lineolatus. Lygus lineolaris reproduced in field beans and completed a single generation. In field beans, adults entered the crop in late July, corresponding to growth stages from late vegetative to pod initiation, and females laid eggs in the crop. Nymphs hatched and developed and were most numerous at the seed development and seed filling stage. At seed maturity, late instar nymphs and adults were present. In soybeans, L. lineolaris reproduced but nymphs had poorer survival than in field beans. Late in the season, adult numbers greatly increased in field beans and soybeans, partly due to immigration of adult Lygus bugs from early‐maturing crops. Field beans and soybeans appeared to be a transient host for A. lineolatus. There were no effects on yield quality or quantity associated with the numbers of plant bugs seen in field surveys. In laboratory and field cages, the type of injury from L. lineolaris feeding differed among plant growth stages but not between nymphs and adults, although nymphs generally were more injurious. At flowering to pod initiation, abortion of buds, flowers or pods was the most common response to feeding injury; pod abortion did not occur when injury occurred at later growth stages. Sometimes abortions resulted in reduced yield quantity, but sometimes plants compensated for the injury. No loss of seed quality occurred from feeding at this stage. During seed development and filling, feeding injury most frequently affected the vascular supply to filling seeds, resulting in shriveled seeds and pods at harvest, and consequent reduced total harvested seed weight. At seed maturity, direct seed injury, involving penetration of the testa and loss of cotyledon tissue, was the most frequent injury and resulted in pits in the seed coat at harvest. There was no loss in yield quantity when feeding occurred at seed maturity, but seed pitting reduced yield quality. / May 2016
57

Relações no mercado internacional de soja em grão: Preços, volatilidades e fluxo de informações / Linkages in the World Soybean Market: Prices, volatilities and information flow

Silva, Rodolfo Margato da 01 February 2013 (has links)
Este trabalho examina relações de preço e volatilidades entre os contratos futuros de soja em grão negociados nos Estados Unidos, China, Brasil e Argentina ao longo do período delimitado entre 2002 e 2011. Os principais resultados mostram que os preços norteamericanos ainda possuem um papel dominante para explicar as variações de preço nos mercados internacionais. Outros resultados também indicam conexões mais fortes entre os preços na bolsa chinesa de Dalian e nos demais mercados, especialmente após 2006. Esta constatação sugere que o mercado chinês se tornou mais integrado ao mercado global de soja em grão em anos recentes, o que reflete a crescente participação da China no comércio internacional da commodity e o desenvolvimento de seu contrato futuro. Em termos de transmissão de volatilidade, o contrato futuro norte-americano teve papel de referência ao promover o contágio para os mercados futuros de Brasil e Argentina em praticamente todos os intervalos de tempo definidos na pesquisa; além disso, movimentos de volatility spillover do mercado dos Estados Unidos para a bolsa chinesa de Dalian ocorreram somente entre 2009 e 2011, ratificando a maior conexão do mercado asiático nos últimos anos. Ainda, Brasil e Argentina mostraram fortes relações com o mercado chinês, fruto do estreitamento comercial, e ao mesmo tempo foram nitidamente impactados pela estrutura de preços e por choques ocorridos na bolsa norte-americana. A despeito da caracterização do contrato futuro dos Estados Unidos como líder na precificação da soja em âmbito mundial, o presente trabalho expõe a grande parcela de importância da bolsa chinesa na definição do preço eficiente de longo prazo da soja em grão, e confirma Brasil e Argentina como seguidores no sistema internacional de ajuste de preços. Através da comparação entre modelos com diferenças acerca da utilização de preços de fechamento ou de abertura da China, o conjunto com cotações de fechamento apresentou maior número de relações de preço e processos de transmissão de volatilidade significativos. A grande contribuição deste estudo corresponde ao resultado sintético de que os principais players do mercado internacional de soja em grão são bastante conectados através de movimentos de preços, volatilidades e fluxos de informação, e que as conexões entre eles se tornaram mais fortes com o passar dos últimos anos. Em termos de aplicação prática, o estudo apontou que os agentes do mercado internacional de soja em grão que acompanharem os movimentos do contrato futuro da China diariamente tendem a realizar transações mais eficientes e lucrativas. / This thesis examines price and volatility linkages between soybean futures contracts traded in United States, China, Brazil and Argentina for the period ranging from 2002 to 2011. The main findings show that U.S. prices still appear to have a dominant role to explain price changes in international markets. Results also indicate stronger linkages between prices in China and in other three markets, especially after 2006. This result suggests the Chinese market has become more integrated with soybean international markets in recent years, which might reflect the growing participation of China in international trade and the development of its soybean futures contract. Regarding volatility spillover, U.S. futures contract had reference position by promoting price contagion to the futures markets in Brazil and Argentina in almost all time intervals defined; moreover, volatility spillovers from U.S. market to Dalian futures market have been observed only from 2009 to 2011, confirming a stronger linkage between U.S. and Chinese markets in the last years. Besides, Brazil and Argentina have shown strong linkages with Chinese market, due to the trade relationship, and at the same time these countries have been impacted sharply by price structure and shocks from U.S. market. Despite the role of U.S. futures contract as a global leader in the soybean pricing process, this study presents the great importance of Chinese market to define the soybean efficient price in the long run, and it confirms Brazil and Argentina as followers in the international system of price adjustment. By comparing models with differences on the use of closing prices or opening prices from Chinese futures market, the set of closing prices presented the largest number of significant price linkages and volatility spillovers. According to the main contribution of this study, the major players in the soybean international market are highly linked through price movements, volatilities and information flow. Results also indicate that linkages between the soybean futures markets have become stronger over the last years. Regarding the practical application, the study pointed that the players of the soybean international market have to observe the movements in the Chinese futures contract daily to perform more efficient and profitable transactions.
58

"Poeira de soja inalada e seu impacto epidemiológico no desencadeamento de alergia respiratória" / Dust of inhaled soy and its epidemic impact in the respiratory allergy

Pinto, Rodolpho José de Carvalho 20 June 2006 (has links)
Introdução: surtos de asma, por poeira da soja, têm sido relatados, havendo casos fatais. Objetivo: correlacionar exposição, sensibilização e alergia respiratória a esta, no Brasil. Métodos: 590 voluntários (testes de punctura e dosagem de IgE específica). Resultados: operários da indústria apresentaram 15% de. sensibilização à soja. Caminhoneiros 22%. Moradores no entorno da indústria 22% enquanto aqueles que residem distantes 6%. .Na região agrícola distante das plantações 13% e em meio à soja 28% com 5% de sensibilizados somente à soja. O percentual de IgE positivas para soja foi 16%. Houve marcante sensibilização aos fungos. Conclusão: A prevalência de sensibilização à soja demonstra o impacto desse tipo de poluição. A sensibilização aos fungos que colonizam a soja estocada não deve ser subestimada / Background: Asthma outbreaks, by soybean dust inhalation, have been reported fatal cases.. Objective: To correlate exposure and sensitization to soybean dust in Brazil.. Methods: 590 volunteers exposed to soy dust. Prick skin tests were performed and specific IgE were measured in sera.. Results: the workers from the oil refinery had sensitization to soy (15%). Truck drivers 22%. Industry neighborhood 22%. and people who live far from this place presented only 6%. People from agricultural area far from the soy plantations 13% and in the middle of the soy 28%.with 5% sensitized only by soybean . Positive IgE was 16 %. Conclusion: a high prevalence of sensitivity to soybean hull demonstrates the impact of this kind of pollution. The sensitization to the fungi which colonize soybean storage can not be underestimated
59

Efeito de diferentes fontes energéticas da dieta sobre a produção de metano ruminal utilizando a técnica de fermentação ruminal ex situ (micro-rúmen) em bovinos / Effect of energy sources ruminal methane production using ex-situ ruminal fermentation technique in bovines

Martins, Maurício Furlan 17 December 2012 (has links)
Problemática mundial levantada nas últimas duas décadas, a geração de gases de efeito estufa (GEE) tem como parcela contribuidora a emissão de metano por ruminantes. O metano, um potente GEE, é produto final do processo fermentativo de bovinos e, por constituir perda no potencial produtivo destes, tem sido objeto de estudo por nutricionistas do mundo todo. Na busca por estratégias para diminuírem as perdas por metano, diferentes dietas, aditivos e manejos nutricionais têm sido empregados. Fontes lipídicas vegetais, como os grãos de soja, contêm alta porcentagem de ácidos graxos insaturados e este tipo lipídio pode colaborar para a diminuição da metanogênese. Em contrapartida, a inclusão de uma fonte rica em pectina (polpa cítrica) pode contribuir para aumento da produção de metano. Assim, objetivou-se com o presente experimento avaliar o efeito de diferentes fontes energéticas da dieta sobre a produção de metano e parâmetros fermentativos em bovinos. O delineamento adotado foi o quadrado latino 3x3 replicado, com período de 16 dias e 3 tratamentos: Controle: Dieta de baixo extrato etéreo (3,50% de EE); Soja: Dieta de alto extrato etéreo (inclusão de 15% de soja grão, com 5,30% de EE); Polpa: Dieta de baixo extrato etéreo e alta participação de pectina (inclusão de 15% de polpa cítrica, com 3,0% de EE). O consumo de matéria seca (CMS) foi obtido pela diferença do ofertado e a sobra da dieta nos últimos seis dias experimentais. O volume de líquido total, o volume de sólido total, o turnover de sólidos e a taxa de passagem ruminal foram obtidos pelo esvaziamento deste orgão, realizado no 11º e 12º dias experimentais, sendo realizado antes e 3 horas após a alimentação matutina. O conteúdo sólido foi retirado manualmente e o líquido com ajuda de bomba a vácuo, sendo estes pesados separadamente. Uma alíquota de 10% foi utilizada para determinar a matéria seca do conteúdo ruminal e corrigir o volume de sólido total. No 16° dia experimental, foi analisado o pH, com auxílio de uma probe de mensuração contínua. Neste mesmo dia foram realizadas coletas do conteúdo ruminal antes, 3, 6, 9 e 12 horas após a alimentação matinal, para a quantificação da produção de ácidos graxos de cadeia curta (AGCC). Também coletou líquido ruminal, com auxilio de bomba a vácuo, para análise de N-NH3. A técnica empregada para mensurar a produção de AGCC e metano foi de fermentação ruminal ex situ, que consiste em incubar frascos tipo penicilina com conteúdo ruminal sólido e líquido, em banho termostático por 30 minutos. Em seguida, a mensuração de metano e AGCC foi realizada por cromatografia gasosa e estimada a perda de energia realtiva (PER). A PER avalia a eficiência da fermentação dos alimentos, ou seja, verifica a perda de metano quando comparada aos outros produtos da fermentação. Os tratamentos apresentaram efeito (P<0,05) para CMS, Turnover de sólido e Taxa de Passagem. A dieta contendo Soja apresentou menores valores para estes parâmetros que as dietas Controle e Polpa. Os tratamentos não diferiram significativamente (P>0,05) para o Volume Sólido Total. As variáveis pH médio e máximo, tempo de pH abaixo de 5,8; 6,0 e 6,2, assim como, área de pH abaixo de 5,8 e 6,2, não diferiram (P>0,05) entre os tratamentos. Entretanto, o pH mínimo foi maior (P<0,05) para dieta contendo Soja em relação à dieta Controle, sem diferença dos dois grupos para polpa cítrica. A área de pH abaixo de 6,0 foi menos elevada (P<0,05) para o grupo soja quando comparado ao grupo controle, sem diferença dos dois grupos para polpa cítrica. Quanto ao nitrogênio amoniacal, não houve diferença (P>0,05) entre os tratamentos. As produções de AGCC totais, acetato e butirato (mMol/Kg/dia) foram mais elevadas na dieta à base de polpa cítrica e diminuída na dieta à base de grão de soja. Nenhuma dos tratamentos alterou a produção de metano ou a PER. A partir disto, essas fontes são indicadas para a utilização em dietas de bovinos, porém, a inclusão dos grãos de soja, alterou o CMS e sua inclusão resultou em mudanças no ambiente ruminal, alterando do perfil fermentativo, não demonstrando alterações na produção de metano e a PER. A inclusão de lipídios na dieta de bovinos pode diminuir a produção de metano, mas esse efeito não é específicos sobre as arqueas metanogênicas e, portanto, não altera a eficiência de fermentação ruminal. Já a pectina pode aumentar a produção de metano, por ter alta fermentabilidade ruminal, sem, contudo alterar a ineficiência deste processo. / Worldwide issue raised in the last two decades, the generation of greenhouse gases (GGE) has, a contributor parcel in the methane emission by ruminants. Methane, a powerful GGE, is the final product of cattle fermentative process and, for representing productive potential loss, has been studied by nutritionist all over the world. In the search for strategies to reduce losses by methane, different diets, additives and nutritional management have been used. Vegetable lipid sources, such as soybean grain contain high content of unsaturated fatty acids and this type of lipid can contribute to methanogenesis reduction. On the other hand, the inclusion of a high pectin (citrus pulp) source in diets can contribute for methane production increase. In this sense, the objective of the present experiment was to evaluate different energy sources in diet on methane production and fermentation parameters in cattle. The design adopted was a replicated 3x3 Latin square with 16 day period and 3 treatments: Control: Low ether extract diet (3.50% of EE); Soybean: High ether extract diet (inclusion of 15% of soybean grain with 5.30% of EE); Citrus pulp: Low ether extract and high inclusion of pectin diet (inclusion of 15% of citrus pulp with 3.0% of EE). Dry matter intake (DMI) was obtained by the difference between the offered and the surplus of the diet at the last six experimental days. Rumen total liquid volume, total solid volume, solid turnover and ruminal passage rate were obtained by the emptying of this organ performed at days 11 and 12 of each experimental period, before and 3 hours after morning feeding. The solid content was manually removed and the liquid by vacuum pulp and both samples weighed separately. A sample of 10% was used to determine dry matter of rumen content and correct total solid volume. At day 16 of experimental period, ruminal pH was determined by a data logger of continuous measurement. At this day, ruminal content sampling was carried out before, 3, 6, 9 and 12 hours after morning feeding for short chain fatty acids (SCFA) production. Rumen fluid was also collected, through vacuum pulp, for ammonia nitrogen determination. The technique applied to measure methane and SCFA production was the ex situ rumen fermentation that consists on the incubation of penicillin flasks with solid and liquid rumen content in a thermostatic bath for 30 min. After, methane and SCFA determinations were carried out by gas chromatography and the relative energy loss (REL) was estimated. The REL evaluates the efficiency of feed fermentation. In other words, verifies methane loss when compared to other fermentation products. It was observed effect of treatment (P<0.05) for DMI, rumen solid turnover and passage rate. Soybean diet had lower values than control and citrus pulp diet in all these parameters. Treatments did not significantly differ (P>0.05) for total solid volume. The variables mean and maximum ruminal pH, time wich pH was under 5.8; 6.0 and 6.2, as well as, pH area under 5.8 and 6.2 did not differ (P>0.05) between treatments. However, minimum pH was higher (P<0.05) in soybean group when compared to control, without difference of two groups to citrus pulp. pH area under 6.0 was lesser (P<0.05) in soybean group compared with control group, without difference of two groups to citrus pulp. For ammonia nitrogen determination, it was not observed difference (P>0.05) between treatments. Total SCFA, acetate and butirate production (mMol/kg/day) were increased in citrus pulp diet and were decreased in soybean diet. No diet altered (P>0.05) methane production or REL. The inclusion of lipids in the diet of cattle can reduce methane production, but this effect is not specific methanogenic archaea on and therefore does not alter the efficiency of rumen fermentation. Already pectin can increase the production of methane, having high fermentability rumen, without however changing the inefficiency of this process.
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Condicionantes de adoção de agricultura de precisão por produtores de grãos / Determinants of Adoption of Precision Agriculture by Grain Producers

Antolini, Leonardo Silva 07 December 2015 (has links)
A utilização de novas tecnologias e a adoção de inovações na agricultura são fundamentais para o estabelecimento dos padrões de produção, pois, além de mitigarem riscos específicos associados a este ramo de atividade, impactam nos resultados agronômicos, econômicos e financeiros do negócio rural. Diversos aspectos derivam dessa discussão e suscitam questões como: Quais são os condicionantes de adoção de Agricultura de Precisão (AP) por produtores de grãos? Qual é o grau de adoção e uso de Agricultura de Precisão? Quais são as características do produtor rural e da fazenda, as principais tecnologias utilizadas e os fatores de maior influência na adoção de Agricultura de Precisão? Qual é a influência das características do produtor, características da fazenda e fontes de informação na adoção de Agricultura de Precisão? Partindo dessas questões de pesquisa, o objetivo geral do trabalho foi identificar os condicionantes de adoção de Agricultura de Precisão por produtores de grãos. Os objetivos específicos foram: mensurar o grau de adoção e uso de AP; caracterizar o produtor rural e a fazenda, as principais tecnologias utilizadas e os fatores de maior influência na adoção de AP; analisar a influência das características do produtor, características da fazenda e fontes de informação na adoção de Agricultura de Precisão. Essa pesquisa é caracterizada como estudo exploratório e descritivo, com aplicação de técnicas de análise quantitativas. Foram realizadas 404 entrevistas presenciais com produtores de soja e milho. A análise dos dados foi feita com a técnica de regressão logística. Constata-se que os condicionantes encontrados são relacionados a características do produtor, como educação e importância da renda da agricultura, a características da fazenda, como área de safrinha de milho, a fontes de informação, como assistência técnica e extensão rural - Emater/Cati, e aos meios de comunicação, como palestras e publicações de universidades. As tecnologias no estágio de Maioria Inicial (Até 50% da população) são análise de solos, aplicação de corretivos e fertilizantes em taxa variável, amostragem de solo em grade (Georreferenciada), mapa de aplicação, piloto automático, aplicação de defensivos em taxa variável, GPS com barra de luz, monitor de colheita e mapa de produtividade. As tecnologias adotadas pelos Pioneiros (Até 16% da população) são semeadura em taxa variável, GPS com correção RTK, sensoriamento remoto (aéreo/satélite/outros) e irrigação de precisão. A única tecnologia somente adotada pelos Inovadores (até 2,5%) foram os sensores de plantas daninhas, pragas e doenças. Por fim, o trabalho sugere temas para estudos futuros. / The use of new technologies and the adoption of innovations in agriculture are critical for the establishment of production standards, because they mitigate specific risks associated with this field of activity, impact on the agronomic, economic and financial results of the rural business. Several aspects derive from this discussion: What are the determinants of adoption of precision agriculture (PA) of grain producers? What is the level of adoption and use of Precision Agriculture? What are the characteristics of the farmer and the farm, the main technologies used and the most influential factors in the adoption of Precision Agriculture? What are the influence of producer characteristics, farm characteristics and sources of information on the adoption of Precision Agriculture? Based on these research questions, the main objective of this study was to identify the determinants of adoption of Precision Agriculture of grain producers. The specific objectives were to measure the level of adoption and use of PA; characterize the farmer and the farm, the main technologies used and the most influential factors in the adoption of PA; analyze the influence of producer characteristics, farm characteristics and sources of information on the adoption of Precision Agriculture. This research is characterized as exploratory and descriptive study, with application of quantitative analysis techniques. 404 face to face interviews were conducted with producers of soybeans and corn. Data analysis was performed with logistic regression. The PA adoption determinants found are related to producer characteristics such as education and importance of agricultural income, the farm characteristics such as second crop corn area (safrinha), sources of information, technical assistance and rural extension - Emater / Cati and the media, such as lectures and university publications. Technologies in Initial Majority stage are soil analysis, application of fertilizers in variable rate, soil sampling grid (Georeferenced), application map, autopilot, application of pesticides in variable rate, GPS with light bar, harvest monitor and productivity map. The technologies adopted by Pioneers are variable rate seeding, GPS with RTK correction, remote sensing and precision irrigation. The only technology only adopted by innovators were the sensors of weeds, pests and diseases. Finally, this research suggested topics for future studies.

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