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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

Desenvolvimento e validação de método multirresíduo para determinação de sulfonamidas e trimetoprim em tilápia por UPLC-ESI-QToF-MS / Development and validation of a multirresidue method for the determination of sulfonamides and trimethoprim in tilapia by UPLC-ESI-QToF-MS

Nunes, Kátia Santos Damacena, 1970- 23 August 2018 (has links)
Orientadores: Felix Guillermo Reyes Reyes, Sonia Claudia do Nascimento de Queiroz / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-23T21:06:24Z (GMT). No. of bitstreams: 1 Nunes_KatiaSantosDamacena_M.pdf: 1068510 bytes, checksum: 7643c5a3077803dd36a9801db74845bb (MD5) Previous issue date: 2013 / Resumo: A aquicultura é hoje o setor de produção mundial de alimentos que apresenta o maior crescimento. Compreende todas as formas de criação de animais e cultivo de plantas aquáticas em água doce, salobra e marinho. Um grande constrangimento para o setor são os surtos de doenças, com uma estimativa global de perdas da ordem de muitos bilhões de dólares por ano. Este fato ocorre devido a que o ambiente aquático é mais favorável a proliferação de bactérias patogênicas, podendo atingir altas densidades em torno dos animais e ser ingeridas durante a alimentação ou durante as trocas gasosas. Assim, o risco de infecções bacterianas na criação de peixes é alto, podendo ser consequência de fatores estressantes tais como falta de higiene, alta densidade de estocagem, baixa qualidade da água, flutuação da temperatura, nutrição inadequada, más práticas de manejo, inadequados procedimentos e métodos de transporte, adaptação ao novo ambiente e captura. Na tentativa de minimizar perdas, antibióticos são administrados, através dos alimentos, aos peixes com fins terapêuticos (tratamento de doença). Devido ao seu baixo custo e relativa eficiência em combater infecções bacterianas mais comuns, as sulfonamidas pertencem a uma classe de antibióticos largamente usada. Trimetoprim é outro agente antibiótico frequentemente coadministrado com sulfonamidas para aumentar, de forma sinergética, a eficiência do tratamento contra uma variedade de infecções bacterianas. Entretanto, o uso de antimicrobianos como agentes quimioterapêuticos tem criado problemas devido ao seu efeito tóxico, desenvolvimento de resistência microbiana, resíduo acumulativo e consequências à saúde pública e ao meio ambiente. O monitoramento dos resíduos de quimioterapêuticos em alimentos tem se tornado prioritário para o controle de resíduos de contaminantes na cadeia de produção de alimentos de origem animal. Nos últimos anos, ocorreu um rápido desenvolvimento de novos métodos analíticos, para a determinação destes resíduos. Dentre os métodos de análise mais promissores, inclue-se a técnica de preparo de amostras denominada QuEChERS ("QuEChERS - Quick Easy Cheap Effective Rugged Safe"), o qual foi empregado neste estudo. Para a quantificação dos resíduos foi utilizada a técnica UPLC-ESI-QToF MS, por se tratar de um método altamente seletivo na determinação de moléculas orgânicas sendo, atualmente, uma das técnicas mais modernas de quantificação de resíduos em alimentos, permitindo níveis de quantificação na ordem de ng/g de matriz. No presente estudo, para fins de desenvolvimento e validação do método analítico foi considerado o limite máximo de resíduo (LMR) estabelecido na União Europeia (EU) (100 ng g-1). O método desenvolvido foi validado en conformidade aos guias de validação da EU e do Ministério da Agricultura Pecuaria e Abastecimento (MAPA) do Brasil, tendo apresentado seletividade sem efeito matriz para as sulfonamidas estudadas. A precisão (intra e interdias) verificada apresentou coeficiente de variação (CV %) menor do que 20 %. Os limites de deteccção (LOD) e quantificação (LOQ) foram 1 ng g-1 e 5 ng g-1, respectivamente. Para as sulfonamidas o valor de CCa variou entre 102,6 e 120,0, e para CCß entre 111,7e 140,1. Para o trimetoprim o valor de CCa e CCß foi de 70,0 e 89,9, respectivamente. Os resultados obtidos indicam que o método é apropriado para a determinação de sulfonamidas e trimetoprim em filés de tilápia / Abstract: The aquaculture is at present one of the food production sectors with the highest expansion. It comprises all forms of animal and vegetal aquatic cultures and plants in the fresh water, brackish and marine environments. A major drawback for the sector is the disease outbreaks, with estimated overall losses of several billion dollars per year. This fact occurs because the aquatic environment is more favorable to pathogenic bacteria, regardless of the animal specie, they could reach high densities around them and be ingested during feeding or when they ingest water. Thus, the risk of bacterial infections in fish farming is high and may be due to stress factors such as poor hygiene, overcrowding, poor water quality, temperature fluctuation, poor nutrition, poor management practices, careless handling, improper procedures and transport methods, adaptation to the new environment and capture. In an attempt to minimize losses, antibiotics are administered, by means of the food, to fish for therapeutic (to treat disease) purposes, in aquaculture facilities throughout the world. Due to its low cost and effectiveness in overcoming the most common bacterial infections, sulfonamides are a class of widely used antibiotics. Trimethoprim is another antibiotic agent frequently emplyed in conjunction with sulphonamides to increase, synergistically, the power of treatment against a variety of bacterial infections. The use of antibiotics or chemotherapeutics has created problems due to its toxic effects, bacterial resistance induction, cumulative and residual effects to public health and to the environment. The monitoring of veterinary drug residues in food has become a main concern for the control of residues of contaminants in the production chain of animal foods. In recent years, there was a fast development of new analytical methods for determination of these residues. Among the most promising methods of analysis it is found the technique of sample preparation called "QuEChERS - Quick Easy Cheap Effective Rugged Safe", which was used in this study. UPLC-ESI-QToF MS technique was used in the quantification of the residues, since it is a highly selective method for the determination of organic molecules, currently, being one of the most modern techniques for quantifying residues in food, enabling the possibility to quantify residues in the order of ng g-1. In the present study, for the purpose of development and validation of the analytical method it was considered the maximum residue limit (MRL) established in Japan (20 ng g-1), which is lower than that established in the European Union (EU) (100 ng g-1). The method was validated according to the validation guidelines of the EU and the Brazilian Ministry of Agriculture Livestock and Supply (MAPA), having presented selectivity and no matrix effect for the sulfonamides studied. The precision (intra-and interday) showed a coefficient of variation (CV %) less than 20 %. The limits for detection (LOD) and quantification (LOQ) were 1 ng g-1 and 5 ng g-1, respectively. The results indicate that the method is suitable for the determination of sulfonamides and trimethoprim in tilapia fillets. For sulfonamides, the value of CCa varied between 102.6 and 120.0, and 111.7 and 140.1 between CCß. For the value of trimethoprim and CCa CCß was 70.0 and 89.9, respectively. The results indicate that the method is suitable for the determination of sulfonamides and trimethoprim in tilapia fillets / Mestrado / Ciência de Alimentos / Mestra em Ciência de Alimentos
52

Theory of Congruences

Green, Harold Rugby 06 1900 (has links)
This thesis presents a series of theorems along with proofs to establish a theory of congruences.
53

Picloram residues in potatoes and carrots and picloram photodecomposition.

Soniassy, Ranjit Nunderdass January 1970 (has links)
Residues of picloram in four varieties of potatoes, given pre-emergence treatments with picloram at 2 oz per acre and picloram at 2 oz + linuron at 24 oz per acre were determined by electron capture gas chromatography. Average residue levels of 3.9 and 2.7 ppb (fresh weight) were obtained for the picloram and picloram + linuron treatments. This difference was significant at the 1% level. Tuber injury, ranging from formation of corky tissues on the surface to splitting, was observed with the picloram treatments. No such injury was observed with the picloram + linuron treatments. Yields were noticeably higher in the picloram + linuron treatments. The reduced picloram residues could thus be associated with the diluting effect of higher yields which resulted from the addition of linuron. A similar experiment using four varieties of carrots given either pre-emergence or post-emergence treatments with picloram at ½ and 2 oz per acre respectively gave no detectable picloram residues. Using ¹⁴C carboxyl labeled picloram this finding was further investigated and it was shown that picloram was absorbed by the foliage and roots and translocated throughout the whole plant. The leaves accumulated four times more radioactivity than the taproots. The radioactivity in the leaves and taproots was in the form of the parent picloram molecule. The picloram present in the taproot was located mainly in the xylem. A study of the stability of picloram, its potassium salt and its methyl ester under short wave ultraviolet light (253.7 nm) revealed that all three compounds were degraded into several photoproducts. The methyl ester was the least stable, being 85% degraded after one hour exposure. Picloram and its potassium salt were more stable, each being 50% decomposed after one hour exposure. Partial polymerization of all three compounds may also have taken place. / Land and Food Systems, Faculty of / Graduate
54

The use of atrazine in corn production.

Alexander, Phillip C. January 1973 (has links)
No description available.
55

New and improved division algorithms in residue number systems /

Chren, William A. January 1987 (has links)
No description available.
56

Gas chromatographic, mass spectrometric and stable carbon isotope investigations of organic residues in `slab-lined pits' from Arctic Norway

Heron, Carl P., Nilsen, G., Stern, Ben, Craig, O.E., Nordby, C.C. January 2010 (has links)
No / Gas chromatography-mass spectrometry (GC-MS) and bulk carbon isotope determinations have been performed on samples ('cemented organic residues', charcoal, sediment and fire-cracked rock) excavated from twelve slab-lined pits from various locations in Arctic Norway to test the premise that these archaeological features were used for the extraction of oil from the blubber of marine mammals, such as seal, whale and walrus. A wide range of lipid compound classes were detected especially in the cemented organic residues and in the charcoal samples. The presence of long-chain unsaturated and isoprenoid fatty acids together with oxidation and thermal alteration products of unsaturated acids such as dicarboxylic acids, dihydroxyfatty acids and ω-(o-alkylphenyl)alkanoic acids suggests that these features were used for marine oil extraction at elevated temperatures. Notably the location of the hydroxyl groups in the dihydroxyfatty acids provides a record of the positional isomer of the precursor fatty acid and allows confirmation that 11-docosenoic (cetoleic) acid, the most abundant C22:1 isomer in marine oil, was a major component of the original lipid. Further information was provided by the presence of long-chain fatty acyl moieties in surviving triacylglycerols and the presence of cholesterol. A fungal metabolite, mycose (trehalose), was found in all samples apart from a fire-cracked rock and points to microbiological activity in the pits. Bulk isotope analysis conducted on the 'cemented organic residues' is consistent with modern reference samples of blubber and oil from seal and whale. These data provide clear analytical evidence of the function of slab-lined pits in the archaeological record and suggest widespread exploitation of marine mammals for producing oil for heating, lighting and myriad other uses in the past.
57

Bioconversion of sugar cane residues into edible monascus and pleurotus products.

January 1998 (has links)
by Pui-nin Lee. / Thesis submitted in: August 1997. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 141-148). / Abstract also in Chinese. / List of Abbreviations --- p.I / List of Tables --- p.II / List of Figures --- p.III / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Sugar cane --- p.1 / Chapter 1.2 --- Mushroom: Pleurotus pulmonarius --- p.5 / Chapter 1.2.1 --- Fruiting bodies --- p.5 / Chapter 1.2.2 --- Life cycle of the mushroom --- p.6 / Chapter 1.2.3 --- Cultivation --- p.7 / Chapter 1.2.4 --- Nutrition --- p.8 / Chapter 1.2.5 --- Cardiovascular and Renal effects --- p.9 / Chapter 1.2.6 --- Dietary fiber --- p.10 / Chapter 1.2.6.1 --- Physical properties of dietary fiber --- p.10 / Chapter 1.2.6.2 --- Physiological actions --- p.11 / Chapter 1.3 --- Food colorants --- p.13 / Chapter 1.4 --- Quality of food products --- p.14 / Chapter 1.4.1 --- Toxicity studies --- p.15 / Chapter 1.4.2 --- Stability --- p.16 / Chapter 1.4.3 --- Sensory evaluation --- p.18 / Chapter 1.5 --- Secondary metabolism --- p.20 / Chapter 1.6 --- Monascus --- p.24 / Chapter 1.6.1 --- Monascus products --- p.25 / Chapter 1.6.2 --- Monascus products as a functional food --- p.27 / Chapter 1.6.3 --- Monascus pigments --- p.27 / Chapter 1.6.4 --- Factors affect Monascus pigment production --- p.31 / Chapter 1.7 --- Purposes of study --- p.37 / Chapter Chapter 2 --- Materials and Methods --- p.38 / Chapter 2.1 --- Micro-organisms --- p.38 / Chapter 2.2 --- Maintenance of culture --- p.38 / Chapter 2.3 --- Waste Culture medium for production of pigments --- p.38 / Chapter 2.4 --- Chemical analysis of sugar cane residue broth (SCRB) --- p.39 / Chapter 2.5 --- Preparation of inoculum --- p.40 / Chapter 2.6 --- Batch culture for pigment production --- p.41 / Chapter 2.7 --- Fermentor culture for pigment production --- p.44 / Chapter 2.8 --- Cultivation of oyster mushroom --- p.46 / Chapter 2.9 --- Purification and characterization of Monascus pigments --- p.49 / Chapter 2.9.1 --- Extracellular pigments --- p.49 / Chapter 2.9.2 --- Intracellular pigments --- p.50 / Chapter 2.10 --- Toxicity test --- p.56 / Chapter 2.11 --- Sensory evaluation --- p.61 / Chapter 2.12 --- Statistical analysis --- p.62 / Chapter Chapter 3 --- Results --- p.62 / Chapter 3.1 --- Extracellular pigment of screening test --- p.63 / Chapter 3.2 --- Batch culture for pigment production by Monascus purpureus --- p.69 / Chapter 3.2.1 --- Consumption of glucose --- p.69 / Chapter 3.2.2 --- Consumption of sucrose --- p.59 / Chapter 3.2.3 --- Biomass production --- p.69 / Chapter 3.2.4 --- Residual protein content --- p.73 / Chapter 3.2.5 --- pH value of the fermented medium --- p.73 / Chapter 3.2.6 --- Production of crude extracellular pigments --- p.73 / Chapter 3.2.7 --- Production of crude intracellualr pigments --- p.75 / Chapter 3.2.8 --- Total crude pigment yield --- p.75 / Chapter 3.3 --- Fermentor --- p.77 / Chapter 3.3.1 --- "Pigmentation of control group, treatment A and B" --- p.77 / Chapter 3.3.2 --- Nutrition of the biomass from control group and treatment B of fermentor products --- p.80 / Chapter 3.4 --- Production of oyster mushroom --- p.80 / Chapter 3.4.1 --- Biological efficiency of mushroom --- p.80 / Chapter 3.4.2 --- Amino acid profile and total amino acid content of the fruitbidies --- p.87 / Chapter 3.4.3 --- Total dietary fiber content --- p.87 / Chapter 3.4.4 --- "The contents of carbon, hydrogen and nitrogen" --- p.91 / Chapter 3.4.5 --- Sensory evaluation of the mushroom --- p.91 / Chapter 3.5 --- Toxicity --- p.91 / Chapter 3.5.1 --- Acute toxicity --- p.91 / Chapter 3.5.1.1 --- Body weight --- p.95 / Chapter 3.5.1.2 --- Food consumption --- p.95 / Chapter 3.5.2 --- Subacute toxicity --- p.99 / Chapter 3.5.2.1 --- Food consumption --- p.99 / Chapter 3.5.2.2 --- Body weight --- p.99 / Chapter 3.5.2.3 --- The organ weight to body weight ratios --- p.99 / Chapter 3.5.2.4 --- The glutamate-pyruvate transaminase (GPT) and glutamate- oxaloacetate transaminase (GOT) level in blood serum --- p.103 / Chapter 3.6 --- Analysis of Monascus pigments from fermentor system by HPLC and spectrophotometry --- p.108 / Chapter 3.6.1 --- Extracellular pigment from control group --- p.108 / Chapter 3.6.2 --- Extracellular pigment from the group supplemented with 1 % MSG --- p.108 / Chapter 3.6.3 --- Intracellular pigment --- p.111 / Chapter 3.6.3.1 --- Standard of intracellular pigments (conventional pigments) --- p.111 / Chapter 3.6.4 --- Intracellular pigments extracted from SCRB group --- p.111 / Chapter 3.6.5 --- Intracellular pigment extracted from SCRB with 1 % MSG --- p.115 / Chapter 3.7 --- Qualitative and quantitative of the extracellular and intracellular pigments --- p.118 / Chapter 3.8 --- Detection of citrinin by HPLC --- p.123 / Chapter Chapter 4 --- Discussion --- p.128 / Chapter 4.1 --- Screening test --- p.128 / Chapter 4.1.1 --- Batch culture system --- p.128 / Chapter 4.2 --- Toxicity test of crude extracellular pigment --- p.129 / Chapter 4.2.1 --- Acute toxicity --- p.129 / Chapter 4.2.2 --- Subacute toxicity test --- p.130 / Chapter 4.2.3 --- Organ to body weight ratios and cytotoxicity --- p.131 / Chapter 4.3 --- The two new water soluble pigment --- p.132 / Chapter 4.4 --- Extraction and purification of Monascus pigments from fermentor system --- p.133 / Chapter 4.4.1 --- Qualitative and quantitative of the intracellular and extracellular pigments --- p.133 / Chapter 4.5 --- Nephrotoxic-citrinin --- p.134 / Chapter 4.6 --- Oyster mushroom cultivation --- p.135 / Chapter 4.6.1 --- Fruiting yield (biological efficiency) --- p.136 / Chapter 4.6.2 --- Amino acid content --- p.136 / Chapter 4.6.3 --- Total dietary fiber content --- p.137 / Conclusion --- p.139 / References --- p.141 / Appendix
58

Os Poderes regulador e fiscalizador do estado e os reflexos no gerenciamento de resíduos de serviço de saúde : uma comparação entre normas e práticas brasileira e portuguesa / The State government for standardization and control and the reflections on the health residue management: a comparison between Brazilian and Portuguese standards and practices.

Carmen Sylvia Coutinho de Oliveira 26 February 2010 (has links)
O crescimento desordenado, o consumo desenfreado e as constantes alterações climáticas são aspectos que não podem mais ser desconsiderados, assim como o consequente acúmulo de resíduos, advindos destas características em boa parte do mundo. A capacidade da Administração Pública em regulamentar e fiscalizar as atividades poluidoras tem sido e será, cada vez mais, um grande desafio. Por isso, o presente trabalho se incumbiu de uma análise comparada entre as normas e práticas brasileira e portuguesa, considerando Portugal como Estado-Membro da União Europeia. O resultado foi a identificação de uma série de necessidades de adequação na regulamentação, controle e, principalmente, no processo fiscalizatório brasileiro. / The disorganized development, the unrolled consumption and the constant climate changes are aspects that cannot be ignored nowadays, such as the residue accumulation resulted from those characteristics all over the world. The capacity of the State to regulate and control the polluted activities has been and will be, even more, a great challenge. The following work proposed to realize a compared analysis between the Brazilian and Portuguese standards and practices, considering Portugal as a Member-State in European Union. The result was an identification of a series of needs in the regulation and control, mainly, in the Brazilian control process.
59

The influence of some spray materials on the chlorophyll content of apple leaves

Campbell, Ronald Wayne. January 1946 (has links)
Call number: LD2668 .T4 1946 C3 / Master of Science
60

Den lilla kemifabriken : En studie för att undersöka om nyttan av skogsrester kan ökas i norra Sveriges inland

Häggkvist, Sofie January 2016 (has links)
The background of this work is to suggest ways to take care of branches and tops of trees that today are left out in the north of Sweden after logging because it has to low value to be worth transporting. A solution to this is to place small chemical factories in the sparsely populated areas in the inland of Norrland that can take care of the forest residues and break it into valuable chemicals directly in the forest an then transport it to a market. The aim of this work was to find out if it´s a good idea to invest in these small chemical factories in the north of Sweden. This study has been carried out using literature study and interviews of key people. The largest part of the result comes from the interviews. The results of this study show that the small chemical factory is a good idea. Forest residues contains many valuable substances that should be greater used today. The results section of the report describes various factor that are crucial for the small chemical factory and these are: the products that can be produced, what technology that is suitable, if there is an market, who should be taking care of the factory and how the inland endurance will be affected. The conclusions that can be drawn from the study is that the small chemical factory should produce high-grade-sary chemicals directed at the chemical market. It may also be noted that there is existing technology that can be used in the factories, what has been done in the laboratories today can be implemented in the factory. The market will obviously depend on which product that will be produces, but finding a suitable market should not be impossible. The inland endurance will be positively impacted, among other things, the social endurance is enhances when these small chemical factories creates job opportunities in the inland and it can lead to decreasing the emigration.

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