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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.
491

The effect of a supplemental trace mineral injection on developing beef bull and heifer reproduction

Kirchhoff, Alissa A. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Karol E. Fike / Trace mineral supplementation is necessary for proper reproductive success. Little research has evaluated the effect of an injectable trace mineral product, in conjunction with a dietary mineral supplementation program, on reproduction. This thesis includes two separate studies evaluating the use of an injectable trace mineral product, in addition to a dietary mineral program, on the reproductive success of yearling bulls and heifers. In the first study, we hypothesized that when dietary trace mineral needs are met, administration of an injectable trace mineral product to developing beef bulls would cause a short-term increase in circulating trace mineral concentrations, but not alter semen quality nor ability to pass a breeding soundness examination. Trace mineral treatment did not affect scrotal circumferences and BW of bulls throughout the trial (P [equal to or greater than] 0.20). Trace Mineral bulls had greater (P [equal to or less than] 0.0001) trace mineral concentrations at 8 h post-treatment than Control bulls. Semen trace mineral concentrations on d 42 and 91 were similar (P [equal to or greater than] 0.52) between treatments. Sperm parameters improved (P [equal to or less than] 0.003) from d 42 to 91, but did not differ (P [equal to or greater than] 0.06) between treatments. A similar (P = 0.94) percentage of Trace Mineral (67%) and Control (68%) bulls passed a BSE 91 d post-treatment. In the present study, supplemental trace mineral injection was successful at raising circulating trace mineral levels, but did not alter semen trace mineral levels nor improve semen quality. In the second study we hypothesized that when dietary trace mineral needs are met, the use of an injectable trace mineral product in developing heifers would not affect pregnancy rates at single service fixed-time artificial insemination (FTAI). Trace Mineral heifers had greater (P = 0.02) pregnancy rates (51.28%) than Control heifers (25.58%). The percentage of Trace Mineral (30.77%) and Control heifers (47.50%) that displayed estrous behavior prior to FTAI as indicated by a red estrous detection patch was not different (P = 0.13) between treatments. In the present study, despite dietary trace mineral requirements being met, use of an injectable trace mineral injection improved pregnancy rates following FTAI, but did not affect estrous behavior.
492

Make or buy, feasibility of intermediate good production

Davis, Mark A. January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Daniel M. O'Brien / In the manufacturing process one decision that is common to all industries is the sourcing of intermediate goods used in production. The decision to make internally verses to outsource can affect a firm's comparative advantage and increased company profits. This project deals with sourcing trace minerals used in the production of feed for the commercial production of food animals in the United States. From looking at the sources of minerals to the industry to the current market structure of the trace mineral production industry in the U.S. the question is asked whether trace minerals can be sourced differently for the client to gain this advantage. The specific objective of this research project is to determine whether it is more profitable either to purchase or manufacture trace mineral blends for use in feed ration formulations for a number of plants owned by a representative livestock feed company in western Kansas. The company has several feed plants in operation in the central Great Plains region. Does the company have enough volume of trace mineral usage to enable it to profitably produce its own mineral blends at one of its feed plants? If trace minerals can be profitably produced by the company, it will lead to a decrease in feed production cost for all of its plants. It is possible that this study will show that there is a large enough degree of consolidation in the U.S. mineral blending industry that there is little or no "room" or opportunity available in the competitive raw ingredient market to increase margin by self-producing trace minerals verses outsourcing. The rationale behind this perspective is that the supply of trace mineral blends is controlled tightly by a few existing suppliers / manufacturers who have enough market power and the subsequent ability to limit the entry of new firms. The raw ingredients required to produce these blends could not be purchased economically enough to realize any cost savings in the trace mineral production process.
493

Determinacao de elementos em baixa concentracao e em concentracao de tracos em amostras de magnesita, por analise por ativacao

SEPULVEDA MUNITA, CASIMIRO J.A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:50Z (GMT). No. of bitstreams: 1 00023.pdf: 1054827 bytes, checksum: 051f292ba75d9989421dce6e25e0477e (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
494

Carreadores espectroquimicos e o efeito matriz .Contribuicao ao estudo da analise espectrografica de impurezas gerais ao nivel de tracos em compostos de torio nuclearmente puros

LORDELLO, ANTONIO R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:09Z (GMT). No. of bitstreams: 1 00047.pdf: 2357991 bytes, checksum: 7efde71ce048d76ea8a55b1614ed5669 (MD5) / Tese (Doutoramento) / IEA/T / Instituto de Química - Universidade de São Paulo - IQ/USP
495

Determinacao espectrografica de elementos tracos em aluminio metalico

CHARBEL, MARIA Y. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:31:29Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:44Z (GMT). No. of bitstreams: 1 01374.pdf: 1542007 bytes, checksum: 9a1db046355abdc64e86caa4294db3de (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
496

Estudo da determinacao de elementos traco em cabelos humanos pelo metodo de analise por ativacao com neutrons / Trace element determination study in human hair by neutron activation analysis

FRAZAO, SELMA V. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:47Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
497

Identifying communications of running programs through their assembly level execution traces

Huang, Huihui 28 May 2018 (has links)
Understanding the communications between programs can help software security engineers understand the behaviour of a system and detect vulnerabilities in a system. Assembly-level execution traces are used for this purpose for two reasons: 1) lack of source code of the running programs, and 2) assembly-level execution traces provide the most accurate run-time behaviour information. In this thesis, I present a communication analysis approach using such execution traces. I first model the message based communication in the context of trace analysis. Then I develop a method and the necessary algorithms to identify communications from a dual trace which consist of two assembly level execution traces. A prototype is developed for communication analysis. Finally, I conducted two experiments for communication analysis of interacting programs. These two experiments show the usefulness of the designed communication analysis approach, the developed algorithms and the implemented prototype. / Graduate / 2019-05-11
498

Variações espaciais e temporais de nutrientes dissolvidos e metais traço na área portuária da cidade do Rio Grande (estuário Lagoa dos Patos - RS)

Barbosa, Fabiana Gonçalves January 2006 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Oceanografia Física, Química e Geológica, Instituto de Oceanografia, 2006. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2013-02-11T18:24:39Z No. of bitstreams: 1 2006_fabiana_barbosa.pdf: 1776412 bytes, checksum: 1983355c08ebff62770a80ecc0896046 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-06-11T21:35:03Z (GMT) No. of bitstreams: 1 2006_fabiana_barbosa.pdf: 1776412 bytes, checksum: 1983355c08ebff62770a80ecc0896046 (MD5) / Made available in DSpace on 2013-06-11T21:35:03Z (GMT). No. of bitstreams: 1 2006_fabiana_barbosa.pdf: 1776412 bytes, checksum: 1983355c08ebff62770a80ecc0896046 (MD5) Previous issue date: 2006 / Os estuários são áreas preferidas para a ocupação e urbanização devido a sua localização e importância sócio-econômica. Este tipo de ambiente é vulnerável ao lançamento de inúmeros compostos orgânicos e inorgânicos através de efluentes domésticos e industriais. O Canal de Acesso ao estuário da Lagoa dos Patos, sofre impactos diretos e indiretos, o que pode levar a uma possível deterioração ambiental. Monitoramentos no canal e suas áreas adjacentes são necessários, para a identificação do estado atual da qualidade ambiental principalmente nas áreas de influências diretas e indiretas das atividades portuárias. O objetivo do presente estudo é avaliar de forma espacial, sazonal e temporal as variações nas concentrações totais de metais traço (cádmio, cobre, chumbo e zinco) e de nutrientes dissolvidos (amônio, nitrato, nitrito e fosfato) em águas superficiais do Canal de Acesso (Canal do Rio Grande) ao estuário da Lagoa dos Patos, particularmente na área portuária da cidade do Rio Grande (Porto Novo, São José do Norte e Super porto). Neste estudo foram utilizados os dados obtidos de 5 relatórios técnicos realizados ao longo do eixo do canal, no período compreendido entre 1988 a 2004. A avaliação das concentrações dos nutrientes dissolvidos e metais traço indicou que ocorrem variações espaciais, sazonais e temporais, dependendo principalmente das condições metereológicas e hidrológicas da região, além das diversas influências antrópicas presentes no estuário da Lagoa dos Patos. De maneira geral, os nutrientes e os metais traço no Canal de Acesso apresentaram concentrações abaixo dos limites recomendados pela FEPAM e CONAMA. As concentrações de metais traço mostraram um decréscimo após o início das operações de dragagem de sedimentos no estuário, indicando a importância deste processo na remoção destes elementos do meio ambiente. / Estuaries are preferential areas for occupation and urbanization due its localization and socio-economic importance. This environment is vulnerable to the introduction of organic and inorganic compounds through domestic and industrials effluent. The access canal of the Patos Lagoon estuary, suffers from direct and indirect impacts, and can lead to a possible ambient deterioration. Monitoring studies in the canal and its adjacent regions is necessary to stablish the current state of the environment quality mainly in areas of direct and indirect influences of port activities. The aim of the present study is to evaluate spatially, seasonally and temporally variations of the total concentrations of trace metals (cadmium, copper, lead and zinc) and dissolved nutrients (ammonium, nitrate, nitrite and phosphate) in superficial waters of the Patos Lagoon estuary, particularly the region influenced by the Rio Grande Harbour (Porto Novo, São José do Norte and Superporto). Data between 1988 and 2004 were obtained from 5 technical reports. The assessment of dissolved nutrients and trace metal concentrations indicated that variations occur according the location, meteorological and hydrological conditions of a region, and antropic influences. Results showed that the nutrients and metals concentrations in the canal are below FEPAM and CONAMA recommended limits. Trace metals concentrations showed a decrease, after the beginning of sediment dredging operations in the estuary, showing the importance of this process in the removal of these elements from the environment.
499

Determinacao de elementos em baixa concentracao e em concentracao de tracos em amostras de magnesita, por analise por ativacao

SEPULVEDA MUNITA, CASIMIRO J.A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:50Z (GMT). No. of bitstreams: 1 00023.pdf: 1054827 bytes, checksum: 051f292ba75d9989421dce6e25e0477e (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
500

Carreadores espectroquimicos e o efeito matriz .Contribuicao ao estudo da analise espectrografica de impurezas gerais ao nivel de tracos em compostos de torio nuclearmente puros

LORDELLO, ANTONIO R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:09Z (GMT). No. of bitstreams: 1 00047.pdf: 2357991 bytes, checksum: 7efde71ce048d76ea8a55b1614ed5669 (MD5) / Tese (Doutoramento) / IEA/T / Instituto de Química - Universidade de São Paulo - IQ/USP

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