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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

A two-dimensional omega equation for the 1000-700 MB layer with diabatic heating,

Ferrentino, Peter S. January 1966 (has links)
Thesis (M.S.) - U.S. Naval Postgraduate School, 1966. / Bibliography: leaves 57-[58].
52

Zur Analytik von Lipiden im Hunde- und Katzenserum nach Fütterung ungesättigter Fettsäuren

Zorn, Natalie. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2004--München.
53

The effect of all-trans retinoic acid and fatty acids on MCF-7 breast cancer cell progression a thesis /

Brown, David Adam. Hawk, Susan Nicole. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on November 13, 2009. Major professor: Susan Hawk. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture, with specialization in Food Science and Nutrition." "October, 2009." Includes bibliographical references (p. 40-46).
54

Fleromättade fetter, torra ögon och Sjögrens syndrom : Kan en kost rik på omega 3 och 6 lindra symtomen vid Sjögrens syndrom och torra ögon?

Granberg, Ebba January 2017 (has links)
Introduktion: Torra ögon (DES) och Sjögrens syndrom (SjS) är inflammatoriska sjukdomar som drabbar ögonen. DES drabbar tårkörtelns funktionella del vilket ger ögonsmärta och suddig syn. SjS är en kronisk autoimmun sjukdom som ger skada på tår- och salivproducerande körtlar. Det leder till kliniska symtom i form av mun- och ögontorrhet. Essentiella fettsyror bildar proinflammatoriska och antiinflammatoriska cytokiner som kan hjälpa vid behandling av dessa sjukdomar. Metod och syfte: En litteraturstudie genomfördes för att ta reda på om fleromättade fetter kan lindra symtomen vid SjS och DES. Resultat: Resultaten för studierna visade resultat på OSDI, Schirmers test, BUT, IL-17, tårosmolaritet, tårvolym, ostimulerat salivflöde, stimulerat salivflöde, sonderingsdjup, PGE1, van Bijstervelds poäng och flourscein infärgning. Diskussion: Resultatet visar signifikanta skillnader för vissa doser av n-3 och n-6. Det som skiljer resultaten åt är de olika doserna av fettsyror samt vad dess placebokontroller intog. OSDI visade främst skillnader på de patienter med DES men endast på en grupp med SjS som intog n-3 för behandling av torr mun. Schirmers test och BUT visade en ökning hos patienterna med mild och måttlig DES men inte på patienterna med SjS. Patienterna med SjS visade förbättringar på stimulerat salivflöde och OSDI för torr mun samt PGE1 nivåer och flourscein infärgning samtidigt som en del studier inte visade några signifikanta förbättringar på några mätvariabler. Det kan grunda sig i intaget av fettsyror, sjukdomstillstånd eller längden på behandling. Slutsats: En del personer kan få förbättrade symtom av att inta n-3 eller n-6 tillskott men skillnaderna är inte alltid statistiskt signifikanta för studierna. / Introduction: Dry eye syndrome (DES) and Sjögren ́s syndrome (SjS) are inflammatory diseases that affect the eyes. DES affects the lacrimal glands functional unit, causing eye pain and blurred vision. SjS is a chronical autoimmune disease that causes damage to tear and salivary glands. It leads to clinical symptoms in the form of mouth and eye irritation. Essential fatty acids form pro-inflammatory and anti-inflammatory cytokines that can help in the treatment of these diseases. Method and purpose: A literature study was performed to study if essential fatty acids can relieve the symptoms of DES and SjS. Results: The results for the studies showed results on OSDI, Schirmer ́s test, BUT, IL- 17, tear osmolarity, tear volume, unstimulated salivary flow, stimulated salivary flow, depth of probing, van Bijsterveld ́s score and flourscein staining. Discussion: The result shows significant differences for certain doses of n-3 and n-6. What separates the results are the different doses of fatty acids and what their placebo controls took. OSDI showed major differences in patients with DES but only in one group of patients with SjS who took n-3 for treating dry mouth. Schirmer ́s test and BUT showed an increase in patients with mild and moderate DES but not in patients with SjS. Patients with SjS showed improvements in stimulated salivary flow, dry mouth OSDI, PGE1 levels and flourscein staining, while some studies did not show any significant improvements in any measurement variables. It may be due to the intake of fatty acids, disease states or the length of treatment. Conclusion: Some people may get improved symptoms of taking n- 3 or n-6 supplements, but the differences are not always statistically significant for the studies.
55

Lipid oxidation in a model system and in meat

Arnold, Andrew Richard January 1989 (has links)
Lipid oxidation is the main factor which limits the shelf-life of meat when held under frozen storage. Research undertaken used pork phospholipid liposomes as a model for studying lipid oxidation in meat. Oxidation was followed by monitoring the decrease in the phospholipid unsaturated fatty acyl chains. It was found that the greater the level of unsaturation of the phospholipid fatty acyl chain the greater was their susceptibility to peroxidation. However, the results were not consistent and several reasons for the variation in rate are provided. At ambient temperatures copper (II) was found to be pro-oxidant in the peroxidation of liposomes. At temperatures below 0°C the prooxidant activity of copper (II) was significantly reduced. However copper again became highly pro-oxidant if sodium chloride was present. It is suggested that salt controls the copper ion concentration at sub-zero temperatures as the pro-oxidant activity of copper (II) is reduced on increasing the copper (II) concentration from 0.9 to 90 ppm. Other experiments found sodium nitrite and pholyphosphate to act as antioxidant and that liposome structure was an important factor in the rate of peroxidation. Four storage trials on pork burgers were undertaken to determine whether salt was also pro-oxidant in the stability of pork when held under frozen storage. The oxidative deterioration of the meat was followed by the following methods of analysis:- 1. The decrease in the unsaturated acyl chains of both total lipid and phospholipid. 2. The change in the colour parameters of the meat using reflectance spectroscopy. 3. The analysis of neutral lipid oxidation products by HPLC. 4. The organoleptic qualities of the pork using a trained panel of food assessors. The results from these storage trails showed that the deterioration of pork was minimised by storing the burgers at lower temperatures within the range 0 to -30°C. Salt was found to accelerate the oxidative deterioration of both uncooked and cooked pork when stored at -20°C. Nitrite was found to exhibit some antioxidant behaviour and reduce the pro-oxidant effect of salt.
56

Síntese enantiosseletiva de beta-aminoésteres quirais através de sistemas enzimáticos envolvendo transaminases / Enantioselective synthesis of chiral beta-amino ester by enzyme systems involving transaminases

Cruz, Raquel Sabará [UNESP] 04 March 2016 (has links)
Submitted by Raquel Sabará da Cruz null (raqsabara@hotmail.com) on 2016-03-21T22:33:50Z No. of bitstreams: 1 dissertação versão final-impressão.pdf: 2574095 bytes, checksum: 8540d453330bcae116046e55b480b86b (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-22T19:26:18Z (GMT) No. of bitstreams: 1 cruz_rs_me_araiq_par.pdf: 1393236 bytes, checksum: fb9a7d96afc03bc23ad50d07330e227c (MD5) / Made available in DSpace on 2016-03-22T19:26:18Z (GMT). No. of bitstreams: 1 cruz_rs_me_araiq_par.pdf: 1393236 bytes, checksum: fb9a7d96afc03bc23ad50d07330e227c (MD5) Previous issue date: 2016-03-04 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Beta-aminoésteres/ácidos quirais enantiomericamente puros são blocos construtores quirais economicamente importantes para a indústria farmacêutica, de química fina, e agroquímica. As transaminases, também conhecidas como aminotransferases têm emergido como uma importante classe de enzimas com grande potencial na síntese enantiosseletiva desses compostos. Neste trabalho foi avaliada a reatividade de omega-transaminases frente a beta-cetoésteres arílicos (benzoilacetato de etila) e alquílicos (acetoacetato de etila) visando à síntese enantiosseletiva de beta-aminoésteres/ácidos. As enzimas utilizadas neste trabalho foram produzidas no laboratório a partir de plasmídeos contendo genes que codificam omega-transaminases (R) e (S)-seletivas provenientes de diferentes micro-organismos. Essas enzimas juntamente com uma enzima comercial (S)-seletiva foram empregadas em reações de aminação assimétrica utilizando substratos beta-cetoésteres, e na resolução cinética da (R,S)-feniletilamina. Parâmetros como concentração de enzima:substrato, compostos doadores de grupo amino, temperatura e pH foram avaliados visando à otimização dos rendimentos e enantiosseletividade. As enzimas produzidas apresentaram excelentes conversões (> 99 %) nas reações de síntese assimétrica e elevados excessos enantioméricos (> 99 %) em praticamente todas as reações de resolução cinética nas quais o acetoacetato de etila foi empregado como substrato. Por outro lado, nas reações onde o benzoilacetato de etila foi empregado como aceptor de amina, não se observou a formação do produto de interesse. / Optically pure beta-amino esters/ acids constitute economically important chiral building blocks for the pharmaceutical, fine chemical and agrochemical industries. Transaminases, also known as aminotransferases have emerged as an important class of enzymes with great potential in the enantioselective synthesis of these compounds. In this work, was evaluated the reactivity of omega-transaminase against aryl (ethyl benzoylacetate) and alkyl (ethyl acetoacetate) beta-keto esters for the enantioselective synthesis of beta-amino esters/acids. The enzymes used in this work were produced in the laboratory from plasmids containing genes encoding (R) and (S)-selective omega-transaminases from different micro-organisms. These enzymes along with a (S)-selective commercial enzyme were employed in the asymmetric amination reactions using beta-keto esters substrates and kinetic resolution of (R,S)-phenylethylamine. Parameters such as concentration of enzyme:substrate, amino group donors, temperature and pH were evaluated aiming to optimize yields and enantioselectivity. The enzymes produced showed excellent conversion (> 99%) in the asymmetric synthesis reactions and high enantiomeric excess (> 99%) in practically all kinetic resolution reactions in which ethyl acetoacetate was used as substrate. On the other hand, in reactions where the ethyl benzoylacetate was used as amino acceptor, was not observed the formation of the product of interest. / CNPq: 132685/2014-0
57

Reviewing and Evaluating Claims for Dietary Supplements: Omega Q Plus ® Resveratrol

Lim, Fiona, Mayersohn, Michael January 2015 (has links)
Class of 2015 Abstract / Objectives: To determine the effects of the dietary supplement, “Omega Q Plus ® Resveratrol” on cardiovascular health. More specifically, to review randomized controlled trials to determine the effects of resveratrol, coenzyme Q10, and omega-3-fatty acids on lipid levels and blood pressure. Methods: Randomized, double-blinded, placebo-controlled trials were searched using PubMed and Embase. Studies that assessed the effects of either resveratrol, coenzyme Q10, or omega-3 fatty acids on lipid levels and/or blood pressure in humans were included. Studies that did not use less than 1 gram of EPA and DHA were excluded. Data extraction and validity assessment was conducted by one reviewer; validity for trials were assessed using the Potential for Methodological Bias Assessment Tool (PBMAT). Results: A total of 24 studies were included; 11 for resveratrol, seven for coenzyme Q10, and six for omega-3 fatty acids, totaling to 1633 participants combined. Doses ranged from 8 mg to 3,000 mg of resveratrol per day, 100 mg to 200 mg of coenzyme Q10 per day, and 67 mg EPA + 33 mg DHA to 1944 mg EPA + 1686 mg DHA. Results across trials were inconsistent in regards to efficacy on lipid levels and blood pressure. Subjects with metabolic syndrome or hypertriglyceridemia seemed to benefit from omega-3 fatty acids through improvement in triglyceride levels, however effects with healthy patients were less clear. Conclusions: Overall, the interventions demonstrated mixed results in affecting lipid levels and blood pressure. No conclusions can be made at this point about the efficacy of Omega Q Plus® Resveratrol on cardiovascular health. Further research into these dietary supplements need to be conducted in order to assess their efficacy
58

The production of Omega 3 fatty acids by a mixed microalgae culture

Kimono, Diana Agnes January 2013 (has links)
Background and Aim: Microalgae are a potential economical source of omega-3 fatty acids, which are known for their health benefits. Omega-3 fatty acids derived from microalgae are however still expensive due to high costs involved in production. These costs can partly be attributed to cultivation of microalgae in unialgal cultures, which are prone to contamination, difficult to scale up and require stringent control of growth conditions. This study therefore is aimed to investigate the feasibility of using a mixed microalgae culture for the production of omega-3 fatty acids. Methods and materials: The microalgae were grown under uncontrolled conditions in a hanging-bag photo-bioreactor, with only the phosphorus-nitrogen ratio (P:N-ratio) varied. Variations in the different population proportions in the culture were studied and related to the biomass, total fatty acid and omega-3 fatty acid productivity of the culture. Finally, a comparison was made between the results obtained in this study and similar studies found in literature. Results and discussion: The mixed culture used was composed of several green microalgae, whose proportions varied with P:N-ratio, season, and age of the culture. Different interactions between the populations were observable, and these were thought to influence the culture’s biomass, total fatty acids (TFAs) and omega-3 fatty acid productivity. The TFA content of the culture was ~10-20% by the end of the exponential phase, depending on the nutrients supplied. The fatty acids were composed of mostly unsaturated fatty acids, the majority of which were omega-3 fatty acids; C18:3ω3 (up to 50% of TFA), C16:4ω3 (up to 15%) and C18:4ω3 (up to 5%). Other fatty acids observed included C16:0 (up to 25%), C18:1ω9/C18:1ω8 (up to 20%), C18:2ω6 (up to 5%), traces of C18:0, C18:3ω6, C17:0, C16:3ω3 and C16:1ω7 were also detected. The presence of these fatty acids was found to vary depending on season, P:N-ratio, and age of the culture. When compared to studies in the literature, the mixed culture was found to perform better than, or as well as reported studies, where unialgal cultures were cultivated under controlled laboratory conditions. Conclusion: In view of the reported advantages of cultivating mixed cultures, the production of omega-3 fatty acids via such cultures appears attractive. More research however is needed to optimise the culture; study interactions between the organisms and their effect on biomass, total fatty acid and omega-3 fatty acid productivity. Finally, the economic implications of using mixed cultures need to be evaluated as well.
59

Stanovení mastných kyselin v lidských tkáních / Determination of fatty acids in human tissues

Turňová, Ivana January 2017 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Ivana Turňová Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Consultant: prof. MUDr. Zdeněk Zadák, CSc. Title of Diploma Thesis: Determination of fatty acids in human tissues The fatty acids are non-negligible component of lipids as one of the basic nutrients. This thesis in its theoretical part presents above all the group of polyunsaturated fatty acids (PUFA), which are important structural units of the cell membranes, they are also the precursors to several significant biologically active substances. In the human organism PUFA participate in many physiological and pathological processes this way, where they cause the large spectrum of actions. Onwards the thesis describes the gas chromatography method that is used in chemical analysis of lipids for the fatty acid determination as the gold standard. Experimentally, the fatty acid representation was determined in the blood, muscle, heart, liver and kidney among 26 cadavers divided into two groups according to the presence/absence of inflammatory process at the time of death. The data obtained were statistically analysed. The results were descriptively evaluated and there were indicated possible explanations of differences...
60

Stanovení spektra mastných kyselin u pacientů podstupujících léčbu taxany / Determination of the fatty acids spectrum in patients undergoing treatment with taxanes

Kuříková, Barbora January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author of Diploma Thesis: Bc. Barbora Kuříková Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Consultant: prof. MUDr. Zdeněk Zadák, CSc. Title of Diploma Thesis: Determination of the fatty acids spectrum in patients undergoing treatment with taxanes The diploma thesis deals with the determination of fatty acids spectrum in erythrocytes in patients treated with taxanes. The theoretical part describes general features of fatty acids, their synthesis and degradation. Then it is focused on the topic of breast cancer, taxane treatment and negative side effects associated with taxane treatment, especially polyneuropathy. The gas chromatography, which is commonly used in practice, is also described in this part. The experimental part is divided into three parts. The first part describes working process, chromatographic analysis and evaluation of this analysis. In the second part there is comparing of spectrum of fatty acids of patients without and with polyneroupathy. And in the last part there is a comparing of spectrum of fatty acids of patients before taxane treatment, closely after treatment and about month after the treatment. Results of the experimental part are evaluated at the end...

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