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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

Feasibility Analysis of Seed Production for Use in Re-seeding Land Burned in Wildfires in the Great Basin Region of the United States

Young, Benjamin Jay 01 May 2009 (has links)
Native and introduced grass and shrub species are grown for seed production in the Great Basin region of the United States. The purpose of this research is to evaluate the profitability and risk associated with the production of five different species of grasses and shrubs which are used in rehabilitation following wildfires. Enterprise budgets are constructed for both the establishment and production years. Returns above operating costs are compared to other crops produced in the same region. Production and market risks are discussed. Returns and risks are evaluated using an expected value model which compares risk and return between species, as well as risk and return for seven different crop combinations on a simulated 400-acre farm. All five species evaluated are found to be more profitable than other crops grown in the region. However, there are many production and market factors which must be carefully considered prior to investment in grass and shrub seed production.
52

Impact of Irrigation Applications at Soil Moisture Deficits on Plant Development and Yield of Indeterminate and Determinate Soybean Varieties

Brown, Andy J 11 December 2015 (has links)
As the Mississippi River Alluvial Aquifer declines, it is the duty of soybean producers to become more efficient irrigators. Research was established in 2012 and 2013 in the Mississippi Delta to evaluate plant development and yield of an indeterminate soybean variety with irrigation initiated at the R1 producer standard and compared to initiation timings at the R2, R4, and R5 growth stages once a 2” deficit was reached according to the FAO-56 Penman-Monteith model. Research was also conducted to evaluate seeding rates in irrigated and non-irrigated systems in Starkville and Stoneville, MS in 2013 and 2014. These data indicate that delaying irrigation initiation beyond R1 did not adversely affect yield, and in some instances even provided a small yield increase. Irrigation did show consistent yield benefit regardless of initiation timing over a non-irrigated system. No optimum seeding rate in terms of yield or net return was observed across site years.
53

Management Practices for Corn Producers Implementing Early Planting as a Production Strategy

Hock, Matthew W 08 December 2017 (has links)
Producers choosing to implement an early corn planting management strategy often experience several yield limiting biotic and abiotic factors. Field variability, flooding, sub-optimal soil temperatures which leads to poor nutrient uptake, delayed emergence and reduced root growth can limit grain production. Three separate experiments were conducted to address some of the negative effects associated with early corn planting. Experiment 1 evaluated flooding effects on several morpho-physiological traits including root system architecture during early crop development. Hybrids (DKC 6208, Pioneer 1197) were flooded at planting (V0) and growth stages V1, V2, V3 for 0, 6, 12, 24, 48, 96 hours. Plants flooded at V0 11% suffered the steepest decline in collar height. Plants flooded at V2 10% were more susceptible than plants flooded V1 4%. Overall, there was a linear decline in nutrient concentration if flooding occurred at planting. Tissue Na levels were the most affected by flood duration and K was the least affected. Experiment 2 evaluated biologic compounds developed to increase immobile nutrients P and K to improve fertilizer use efficiency and provide slow developing roots essential nutrients. The effectiveness of microbial products (B-300, QR, Mammoth, EM-1) with/without starter fertilizer influenced yield, emergence, plant growth, and nutrient uptake. Biologic seed treatments compared to the control, resulted in a positive yield advantage for all treatments. Yields ranged from 37 to 48% higher if biologic compounds were applied. On average, yields increased from 26 to 38% after starter fertilizer was added to the biologic compounds. Phosphorus levels at VT were significantly higher for QR and K content was higher for B300, SF-B300, QR, Mamm, and SF-Mamm compared to the control. Experiment 3 addressed soil physical/chemical properties affecting plant development and there yield plant density relationship. On average, yields significantly increased 40% as plant population increased from 49,400 to 103,740 plants ha−1. Based on the quadratic model agronomically yields would be highest at 61,360 plants ha−1. Correlation analysis among yield and soil physical and chemical properties revealed positive correlations for grain yield, sand% (r2 = 0.42), soil K (r2 = 0.17) soil Na (r2 = 0.46), and soil P (r2 = 0.49).
54

Evaluation of economics and management in Mid-South soybean production

Turner, Richard 07 August 2020 (has links)
Two studies were conducted from 2017 – 2019 at Stoneville, MS the first was to determine optimum seeding rates on single and twin row configuration during both late and early planting dates. The second study was to compare two row configurations with two planting populations (whole plot) but add management strategies (subplots) within each whole plot. From this data, yield optimization could be reached within each system that likely encompasses everything a producer in the Mississippi Delta could encounter during a growing season. Soybean seed from this data was analyzed for protein, oil, and fatty acid composition to determine which systems produce greater seed quality in terms of seed composition. Normal (non-symptomatic) and seed visually infected with purple seed stain (PSS) were compared to determine how infected soybean seed compared to normal soybean seed. Both seed (infected and non-symptomatic) were compared by measuring seed composition, germination, and vigor. During 2018 and 2019 at Verona, MS the same whole plot with subplot test was used but at this location under rained conditions. Soybean grown under rained conditions is a common practice in that particular region of the state (Northeast) so treatments were designed to be useful to producers in that area.
55

CROSS-INTERACTION AND INHIBITION OF AMYLOID POLYPEPTIDE AGGREGATION

Hu, Rundong 31 August 2018 (has links)
No description available.
56

Multiscale Molecular Simulations of Cross-sequence Interactions between Amyloid Peptides

Zhang, Mingzhen January 2017 (has links)
No description available.
57

Seeding Rate Effects on Durum Grain Protein Concentration

Ottman, Michael J. 10 1900 (has links)
It has been observed in other wheat growing regions that stands that are thin rarely have problems with low grain protein. The purpose of this study was to determine if this is indeed the case in Arizona. A study was conducted at Maricopa where the durum varieties Duraking, Minos, and Turbo were sown at rates from 30 to 360 lbs seed/acre. Seeding rate had no effect on grain protein or yield in this study. The reported effects of thin stands on grain protein may be related to low yield rather than seeding rate per se.
58

Row Spacing and Direction Effects on Yield, Water Use, Tillering and Light Interception of One-Irrigation Barley

Ottman, M. J. 10 1900 (has links)
The one-irrigation barley variety Solum is adapted to wide row spacing, and sometimes yields higher in wide compared to narrow spacing. This study was initiated to determine the effect of row spacing and direction on Solum water use and yield components. Solum barley was planted at the Marana Agricultural Center at 6, 12, 18, and 24 inch row spacings in north-south and east -west rows in late November and late -February or early March over 2 growing seasons. Row spacing and direction had little effect on yield and yield components, water use, tillering, and light interception. Nevertheless, in some instances narrow row spacing resulted in more heads that were smaller and had lighter kernels than wide row spacing. We measured greater soil water depletion for the narrow row spacings at the late planting date one year due to greater stem density. The narrow rows intercepted more light than wide rows and the wide rows intercepted more light at solar noon in east-west compared to north -south rows. We were not able to confirm the theory that soil water is conserved in wide rows for use at more critical stages later in the season.
59

Seeding de casa colaborativa na perspectiva do design estratégico

Michelin, Coral 20 June 2017 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-08-09T13:29:04Z No. of bitstreams: 1 Coral Michelin_.pdf: 6099049 bytes, checksum: 3a582fc3442bc9e30175c9ff88e828e4 (MD5) / Made available in DSpace on 2017-08-09T13:29:04Z (GMT). No. of bitstreams: 1 Coral Michelin_.pdf: 6099049 bytes, checksum: 3a582fc3442bc9e30175c9ff88e828e4 (MD5) Previous issue date: 2017-06-20 / Nenhuma / Em Porto Alegre estão surgindo espaços compartilhados de trabalho, chamados de Casas Colaborativas, que promovem, com suas atuações, uma visão renovada de bemestar social na cidade. São territórios formados por atores dos mais diversos, principalmente aqueles inseridos na economia criativa, que desenvolvem projetos e atividades com potencial para desencadear inovação social. O Design Estratégico para inovação social trata de processos projetuais para solucionar problemas complexos e se aproxima do contexto identificado como uma abordagem para fortalecer o potencial das Casas Colaborativas. Usando o viés metaprojetual do Design buscou-se responder ao problema que se apresenta: quais são as diretrizes estratégicas necessárias para promover a difusão de Casas Colaborativas? Entendendo que, quanto mais organizações como essas na sociedade, mais inovação social poderá nela ser gerada. A partir dessa questão formulou-se o objetivo geral deste trabalho, que consistiu em elaborar as diretrizes estratégicas para o Seeding de Casas Colaborativas; considerando Seeding como uma estratégia para multiplicação de sistemas complexos de natureza social que geram, promovem ou trabalham com inovação social. A relevância do estudo se dá para a esfera acadêmica, ao avançar na criação de uma estratégia para multiplicação de inovação social, por meio do Seeding; e para a esfera social, ao fornecer os meios necessários para o fortalecimento de organizações como as Casas Colaborativas, de forma que possam, nos mais variados contextos, inclusive globais, se estabelecerem. A pesquisa exploratória-criativa-aplicada usou a cartografia deleuze-guattariana como direcionamento metodológico, de forma a acompanhar o processo de produção de dados (coleta, apresentação e análise) em três territórios de estudo – Paralelo Vivo, TransLab e Vila Flores – e em um trajeto adicional nos Encontros mensais das Casas Colaborativas. O percurso cartográfico obteve como resultado a criação de sete eixos atencionais e oito estratégias que guiaram o projeto da semente de Casa Colaborativa, composta por uma série de diretrizes estratégicas que fornecem as bases para a criação de uma Casa Colaborativa e, assim, dá início ao processo do Seeding. / Shared working spaces are emerging in Porto Alegre, called Collaborative Houses,which promote with their actions a renewed vision of social welfare in the city. They are territories formed by diverse actors, especially those belonging to the creative economy, who develop projects and activities with potential to trigger social innovation. Strategic Design for social innovation deals with design processes to solve complex problems, approaching the specified context as framework to strengthen the Collaborative Houses potential. Using the Metadesign approach of design we tried to answer the following question: what are the strategic guidelines to necessary to promote the diffusion os Collaborative Houses? Understanding that the more organizations like these in society, the more social innovation is bound to happen in it. From this question the objective of this work was formulated, which consisted in elaborating the strategic guidelines for the Seeding of Collaborative Houses; considering Seeding as the strategy for multiplying complex systems of social nature that generate, promote or work with social innovation. The relevance of the study for the academic field is given through the advancement in the creation of a strategy for the multiplication of social innovation; and for the social field is by providing the means necessary for the strengthening of organizations such as the Collaborative Houses, so that they can establish themselves in the most varied contexts, including global ones. This exploratory, creative and applied research has used Deleuze-Guattarian cartography as a methodological guidance, in order to follow the process of data production (collection, presentation and analysis) in three territories of study – Paralelo Vivo, TransLab and Vila Flores – besides in an additional trajectory in the monthly Collaborative Houses Meetings. The mapping process resulted in the creation of seven attention axes and eight strategies that guided the creation of the seed of Collaborative House, which is composed of a series of strategic guidelines that provide the basis for the establishment of a Collaborative House and, thus, beginning the Seeding process.
60

Niskotemperaturno procesiranje sol-gel mulita / Low Temperature Processing of the SoI-CJel Mullite

Simendić Borislav 12 September 2003 (has links)
<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Mehanizam nastanka mulita zavisi od načina doziranja polaznih oblika reaktanata kao &scaron;to su alumina i silika. Dobijanje mulita sol-gel postupkom je u velikoj meri pobolj&scaron;ano u odnosu na klasično procesiranje zbog mogućnosti homogenog me&scaron;anja AI<sub>2</sub>O<sub>3</sub> i SiO<sub>2</sub> komponenti i kontrole dodataka. Sol-gel metod omogućuje pripremu vrlo homogenih i reaktivnih gelova koji mogu da sinteruju na nižim temperaturama pri čemu se može postići vrlo fina mikrostruktura. U ovom radu koji se odnosio na procesiranje mulita sol-gel postupkom, hipoteza je bila da se na samom početku procesiranja aluminijumovi joni iz alkoholnog rastvora Al-soli uključuju u polimernu gel strukturu koju formira silika. Svrha ovog rada, je proučavanje uticaja procesnih promenjivih, dodatka fluornog jona i &ldquo;seedinga&rdquo; na temperaturu nastanka sol-gel mulita pri čemu se očekuje &scaron;to je moguće niža tempertura nastanka mulita (niža od 980<sup>0</sup>C). Polimerni sol je dobijen u prvom slučaju me&scaron;anjem TEOS-a i aluminijum nitrata nanohidrata koji je prethodno rastvoren u etil alkoholu. U drugom slučaju, u polimerni sol je dodavan fluorni jon u koncentraciji 2 do 5 % mas. u odnosu na očekivani prinos mulita i u trećem slučaju je dodavana različita količina mulitnih klica (2-4 % mas.). Eksperimantalno je potvrđeno da procesne promenljive; pH, temperatura geliranja i R odnos imaju, veliki uticaj na brzinu geliranja i na nastanak mulita. U slučaju dodavanja fluornog jona, potvrdena je hipoteza da fluorni jona na različite načine utiče na mehanizam nastanka mulita, pri čemu u prvom slučaju prisustvo fluornog jona obezbeduje mesta u oblastima razdvajanja granica faza nakon geliranja koja utiču na proces nukleacije. Ova mesta slično procesu kristalizacije stakla, omogućuju lak&scaron;u nukleaciju mulita prilikom njegove transformacije iz gela. Mesta na granici razdvanja faza postaju mesta na kojima se uspostavlja proces heterogene nukleacije &scaron;to je jedan od mogućih načina za snižavanje temperature nastanka mulita. Pored ovoga, dodavanje fluornog jona je doprinelo promeni mulitnih gel struktura, pri čemu je promena brzine hidrolize silike imala za posledicu promenu sadržaja vezane vode u toku geliranja &scaron;to se takođe značajno odražavalo na temperaturu nastanka mulita. Eksperimentalni rezultati termički obradenih gelova su pokazali, da dodavanje lluornog jona u polimerni mulitni sol stvara uslove za snižavanje temperature obrazovanja mulita sve do 890<sup>0</sup>C. U ovom radu je takođe pokazano da mulitne čestice, kao nukleanti pri &ldquo;seeding&quot; procesiranju, doprinose nastanku mulitnog gela koji nakon termičke obrade na 1000<sup>0</sup>C pokazuje veoma finu mikrostrukturu.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>The mechanism of mullite formation depends upon the method of combining the alumina and silica containing reactants. Mullite can be obtained through the sol-gel process and can be greatly improved by the control of some reaction conditions particulaiiy by homogeneous mixing of Al2O3 and SiO2, and controlling of the additions. Sol-gel method allow preparation of very homogenous and reactive gels which can be sintering at low temperature and consequently submicronic microstructure can be reached. In this study of the mullite formation by sol-gel method, the hypothesis was that aluminium ions from alcoholic solulion of its salts incorporate to polymeric silica gel structure. The aim of this work was the investigation of the effect processing variables, fluorine addition and &ldquo;seeding&rdquo;on the temperature of sol-gel mullite formation and to obtain as lower temperature of mullite formation as possible (smaller than 980&deg;C). Polymeric sols, were prepared by the mixing of TEOS and aluminum nitrate nanohydrate dissolved in absolute ethyl alcohol and by adding fluorine ions in the second case from 2 wt.% to 5 wt.% and by different content of mullite seeded (2- 4 wt. %). Experimentally is determined that the processing variables as pH, gelling temperature and R ratio have high influence on the gelling rate and mullite formation. The hypothesis in the case of fluorine addition was that addition of fluorine ions could have different effects on the mechanism of mullite formation; the first it makes the sites at boundary of phase separation regions after gelling which influence at the process of the nucleation. These sites will act as a place for easy mullite nucleation, similar to process of the glass crystallization. The boundaries of the phase separation are the sites for heterogeneous nucleation which is one of the condition for lowering the temperature of mullite formation. Besides, fluorine addition could change the mullite gel structure (by changing the rate of hydrolyses of silica and it could change the content of bonded water during gelling), which should be very important for the temperature of mullite formation, too. The experimental results of heat treated gels showed that the addition of fluorine ion does decrease the temperature of mullite formation (in respect to classical sol-gel mullite processing) up to 8900C. As a nucleant in this study the mullite powder by &ldquo;seeding&rdquo; process contribute to muillite gel formation that after heat treatment up to 10000C showed very fine microstructure.</p>

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