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Sistemas aquosos bifásicos de polietilenoglicol e sais inorgânicos : modelo estatístico / Aqueous two-phase systems of polyethylene glycol and inorganic salts : statistical modelsBraga, Filipe Leôncio, 1985- 26 August 2018 (has links)
Orientador: Mário Noboru Tamashiro / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-26T19:25:53Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Resumo: Modelos termo-estatísticos que tentam reproduzir o comportamento de soluções aquosas de polímeros foram amplamente estudados ao longo dos anos. Entretanto, o número de trabalhos relacionados a sistemas aquosos contendo polímeros e sais adicionados ainda é bem restrito. Na tese desenvolvida, abordamos através de uma modelagem de Flory-Huggins a formação de sistemas aquosos bifásicos contendo cadeias poliméricas longas de polietileno-glicol em misturas contendo sais inorgânicos monovalentes. Dentro da modelagem, a competição entre a formação de ligações de hidrogênio por parte das moléculas de água e os monômeros da cadeia polimérica, além das interações íon-dipolo entre água e os íons dos sais dissociados, desempenham papel fundamental na formação das configurações de equilíbrio. Através de ajustes numéricos de dados experimentais, para cada tipo de sal introduzido na mistura, com previsões do modelo para as menores temperaturas para a formação das duas fases, as chamadas Cloud Point Temperatures (CPT), encontramos um conjunto de quatro parâmetros de interação que possibilitam a reprodução adequada do comportamento contínuo das CPT's em função das concentrações dos solutos / Abstract: Thermal-statistical models that try to reproduce the behavior of aqueous polymer solutions have been extensively studied over the years. However, the number of articles related to aqueous systems containing polymers and added salts is still very restricted. Across the developed thesis, we work with a Flory-Huggins theory to model the formation of aqueous two-phase systems containing long-polymer chains of polyethylene-glycol in mixtures containing monovalent inorganic salts. Within the model, the competition between the hydrogen-bond formation between water molecules and the monomers of the polymer chain, in addition to the ion-dipole interactions between water and the dissociated salt ions play a key role in shaping equilibrium configurations. Through numerical fits of experimental data for each type of salt introduced into the mixture with model predictions for the lowest temperatures for the formation of two phases, so-called Cloud Point Temperature (CPT), we find a set of four parameters of interaction that enable proper representation of the continuous behavior of CPT's as a function of the solutes concentration / Doutorado / Física / Doutor em Ciências
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Biodegradable hydrogels based on water-soluble chitosan for cell transplantGámiz González, Mª Amparo 02 November 2016 (has links)
[EN] The aim of tissue engineering is to develop functional biological substitutes to replace or restore damaged tissues by preparing three-dimensional scaffolds able to accommodate cells plus signaling factors to promote the regeneration of damaged tissue. There is a special interest in developing scaffolds that while providing a favourable environment for cells also possess a degradation rate that can be adapted to the tissue's rate of regeneration. Scaffolds should be porous and possess a pore morphology adapted to the application for which they are designed. They must also be able to hold large quantities of water (hydrogels) while presenting suitable cell/biomaterial interaction.
The aim of this thesis is to create chitosan-based three-dimensional porous structures with tunable degradation rates with particular interest in fast degradation rate. Hydrogels of block-copolymer networks were prepared to crosslink the chitosan (CHT) or carboxymethyl chitosan (CmCHT) with either a hydrophobic polymer of low molecular weight, such as poly(ε-caprolactone), (PCL) or a hydrophilic polymer such as poly(ethylene glycol), (PEG). The hypothesis was that the degradation of the cross-linker polymer leaves behind large water-soluble polymer chains (protonated chitosan or carboxymethyl chitosan).
However, in spite of chitosan's favourable properties, the polymer has relatively slow biodegradation times in enzymatic media that contain lysozyme and even slower in hydrolytic conditions.
Chitosan's physical and chemical properties largely depend on its deacetylation degree (DD). In order to analyze these properties, chitosan was synthesized with various DD ranging from 85% to 45%. Water absorption was seen to rise rapidly as deacetylation was reduced. This would appear to contradict the fact that chitin water absorption (low DD) is much lower than that of chitosan. In order to understand this behaviour, it was analyzed the dependence of the degree of network swelling on the parameters determined by the Flory Rhener theory, the elastic properties of the network and the density of the cross-linking according to the sample's water content.
The thermal stability of chitosan according to its DD was analysed by thermogravimetry. Different methods were applied to obtain the activation energy. Electrospinning was chosen as the porous membrane preparation technique as it provides thin membranes that can be handled with fiber sizes in the order of microns. The influence of the electrospinning and cross-linking processes on the thermal stability of chitosan was analyzed.
Chitosan and carboxymethyl chitosan hydrogels covalently cross-linked with short chains of poly(ε-caprolactone), (PCL) and poly(ethylene glycol) (PEG) were synthesized. The formation of networks was confirmed by solubility tests with appropriate solvents for each polymer. Hydrogels that absorbed large quantities of water were obtained, with values that ranged between 90 and 5000%. The calorimetric tests together with the Studies on the kinetics of hydrolytic and enzymatic biodegradation showed three different systems: CmCHT-PEG system that can be classified as stable hydrogel, CHT-PCL system as semidegradable hydrogel and degradable hydrogels with degradation kinetics in the order of days for the CmCHT-PCL system. Finally, biological studies were carried out on porous CmCHT-PCL hydrogels. Mesenchymal stem cells (MSCs) from pig adipose tissue were then cultivated and the results showed that these networks can be used in the organism in tissue engineering applications with degradation times of around a week. / [ES] La ingeniería tisular tiene como finalidad desarrollar sustitutos biológicos funcionales que reemplacen o restauren los tejidos dañados. Se trata de preparar andamiajes tridimensionales (scaffolds) que sean capaces de albergar células y factores de señalización que favorezcan la regeneración del tejido dañado. Existe un especial interés en el desarrollo de scaffolds que proporcionando un entorno favorable a las células, tengan una tasa de degradación que se adapte a velocidad de regeneración del tejido. Los scaffolds deben ser porosos y poseer una morfología del poro adaptada a la aplicación para la que son diseñados. Deben ser capaces de albergar gran cantidad de agua (hidrogeles) al tiempo que presentan una interacción célula/biomaterial adecuada.
El objetivo de esta tesis es el de crear estructuras porosas tridimensionales basadas en quitosano con velocidades de degradación ajustables con particular interés en velocidades de degradación altas. Se han preparado hidrogeles de redes de copolimeros en bloque entrecruzando el quitosano, (CHT) o el carboximetil quitosano, (CmCHT) con un polímero hidrófobo de bajo peso molecular como la poli(ε-caprolactona), (PCL) o bien con un polímero hidrófilo como es el poli(etilenglicol), (PEG). La hipótesis de trabajo fue que la degradación del polímero que actúa como entrecruzador debe dejar grandes cadenas del polímero (quitosano protonado o carboximetil quitosano) que son solubles en agua.
A pesar de las buenas propiedades del quitosano, el polímero presenta tiempos de biodegradación bastante lentos en medio enzimático conteniendo lisozima y aún más lentos en condiciones hidrolíticas.
Las propiedades físico-químicas del quitosano dependen en gran medida del grado de desacetilación, DD. Con el fin de analizar dichas propiedades se ha llevado a cabo la síntesis de quitosano con DD variando entre 85% y el 45%. Se ha comprobado que la absorción de agua aumenta rápidamente a medida que el grado de desacetilación disminuye. Esto parece contradecir el hecho de que la absorción de agua de la quitina (DD bajo) es mucho menor que la de quitosano. Para entender dicho comportamiento se han analizado los parámetros que determinan la teoría de Flory Rhener, las propiedades elásticas de la red y la densidad de entrecruzamiento en función del contenido en agua de la muestra. La estabilidad térmica del quitosano en función de DD ha sido analizada por termogravimetría. Se han aplicado diferentes métodos para obtener la energía de activación. Como técnica de preparación de membranas porosas se ha elegido el electrohilado, ya que permite obtener membranas delgadas y manipulables con tamaños de fibra del orden de micras. Se ha analizado la influencia de los procesos de electrohilado y entrecruzamiento en la estabilidad térmica del quitosano.
Se han sintetizado hidrogeles de quitosano, y carboximetil quitosano entrecruzados covalentemente con cadenas cortas de poli(ε-caprolactona), y poli(etilenglicol). La formación de las redes se ha confirmado mediante ensayos de solubilidad con buenos solventes para cada polímero. En todos los casos se han obtenido hidrogeles que absorben gran cantidad de agua con valores que oscilan entre 90 y 5000%. Los estudios de las cinéticas de biodegradación tanto hidrolítica como enzimática revelan la obtención de tres sistemas que se pueden clasificar como hidrogeles estables, para los hidrogeles formados por CmCHT-PEG, hidrogeles semidegradables para el sistema CHT-PCL y finalmente hidrogeles degradables con cinéticas de degradación del orden de días, para el sistema CmCHT-PCL. Finalmente se ha llevado a cabo estudios biológicos de los hidrogeles porosos de CmCHT-PCL. Se realizaron cultivos con células mesenquimales del tejido adiposo de cerdo (MSCs). Los resultados han revelado que dichas redes pueden ser utilizadas como sistemas de liberación de células en el organismo con tiempos de degradación / [CA] L'enginyeria tissular té com a finalitat desenvolupar substituts biològics funcionals que reemplacen o restauren els teixits danyats. Es tracta de preparar suports tridimensionals (esquelets o scaffolds) que siguen capaços d'albergar cèl.lules i factors de senyalització que afavorisquen la regeneració del teixit danyat. Hi ha un interès especial en el desenvolupament d'esquelets que, proporcionant un entorn favorable a les cèl.lules, tinguen una taxa de degradació que s'adapte a la velocitat de regeneració del teixit. Els scaffolds han de ser porosos i han de tenir una morfologia del porus adaptada a l'aplicació per a la qual són dissenyats. Han de ser capaços d'albergar una gran quantitat d'aigua (hidrogels) alhora que presenten una interacció cèl.lula/biomaterial adequada.
L'objectiu d'aquesta tesi és crear estructures poroses tridimensionals basades en quitosan amb velocitats de degradació sintonizables amb un interés particular de rutes de degradació altes. S'han preparat hidrogels de xarxes de copolímers en bloc entrecreuant el quitosan o el carboximetil quitosan amb un polímer hidròfob de baix pes molecular com la poli (ε-caprolactona), o bé amb un polímer hidròfil com és el poli (etilenglicol). Es tracta d'aconseguir que quan el polímer que actua com a entrecreuador es degrade, deixe grans cadenes del polímer (quitosan protronat o carboximetil quitosan) que són solubles en aigua.
A pesar de les bones propietats del quitosan, el polímer presenta cinètiques de biodegradació lentes en condicions enzimàtiques quan conté lisozima i encara més lentes en condicions hidrolítiques.
Les propietats fisicoquímiques del quitosan depenen en gran mesura del grau de desacetilació, DD. A fi d'analitzar aquestes propietats, s'ha dut a terme la síntesi de quitosan amb un DD que variava entre el 85% i el 45%.
S'ha comprovat que l'absorció d'aigua augmenta ràpidament a mesura que el grau de desacetilació disminueix. Això sembla que contradiu el fet que l'absorció d'aigua de la quitina (DD baixos) és molt menor que no la de quitosan. Per a entendre aquest comportament s'ha analitzat la dependència del grau d'unflament de la xarxa amb els paràmetres que determina la teoria de Flory Rhener, les propietats elàstiques de la xarxa i la densitat d'entrecreuament en funció del contingut en aigua de la mostra. L'estabilitat tèrmica del quitosan en funció del DD ha sigut analitzada per termogravimetria. S'han aplicat diversos mètodes per obtenir l'energia d'activació. Com a tècnica de preparació de membranes poroses s'ha utilitzat l'electrofilatura, ja que permet obtenir membranes primes i manipulables amb grandàries de fibra de l'ordre de micres. S'ha analitzat la influència dels processos d'electrofilatura i entrecreuament amb l'estabilitat tèrmica del quitosan.
S'han sintetitzat hidrogels de quitosan i carboximetil quitosan entrecreuats covalentment amb cadenes curtes de poli(ε-caprolactona) i poli(etilenglicol). La formació de les xarxes s'ha confirmat per mitjà d'assajos de solubilitat amb bons solvents per a cada polímer. En tots els casos s'han obtingut hidrogels que absorbeixen una gran quantitat d'aigua, compresa en valors que oscil.len entre el 90 i el 5.000%. Els estudis de les cinètiques de biodegradació tant hidrolítica com enzimàtica revelen l'obtenció de tres sistemes que es poden classificar com a hidrogels estables (per als hidrogels formats per CmCHT-PEG), hidrogels semidegradables (per al sistema CHT-PCL) i, finalment, hidrogels degradables amb cinètiques de degradació de l'ordre de dies (per al sistema CmCHT-PCL). Finalment s'ha dut a terme estudis biològics dels hidrogels porosos de CmCHT-PCL. Es van realitzar cultius amb cèl.lules mesenquimals del teixit adipós de porc (MSCs). Els resultats han revelat que aquestes xarxes poden ser utilitzades com a sistemes d'alliberament de cèl.lules en l'organisme amb temps de degradació de l'ordre d'una setm / Gámiz González, MA. (2016). Biodegradable hydrogels based on water-soluble chitosan for cell transplant [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/73070 / TESIS
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Commingling Yarns for Reinforcement of ConcreteKravaev, Plamen, Janetzko, Steffen, Gries, Thomas, Kang, Bong-Gu, Brameshuber, Wolfgang, Zell, Maike, Hegger, Josef 03 June 2009 (has links)
Textile reinforced concrete (TRC) is an innovative composite material, which is being intensely and practice-oriented investigated on national and international level. In the last few years this material has gained increasing importance in the field of civil engineering. In the context of the collaborative research project SFB 532 at the RWTH Aachen University, research was carried out to understand and to predict the behaviour of different yarn structures in fine grained concrete. Based on the results, innovative commingling yarns were made of alkali-resistant glass fibres and water soluble PVA. These hybrid yarns have an open structure, which improves the penetration of the textile reinforcement by the concrete matrix. Hence, the load bearing capacity of TRC structural elements was significantly improved. This paper presents a technique for the production of such commingling yarns for concrete applications. The mechanical properties of the new yarns are determined due to tensile stress tests. The bond behaviour of the commingling yarns was investigated by pull-out- and tensile stress tests on TRC-specimens. The results of the different tests are being presented and briefly discussed.
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Effect of lipid-based formulation on the solubilization patterns if poorly water-soluble drugs.Gude, Manjiri January 2021 (has links)
Poorly water-soluble drugs (PWSDs), to date, require advanced formulation techniques to improve solubility and achieve the required plasma concentration to show a therapeutic effect when orally administered. Lipid-based formulations (LBFs) are an enabling strategy that is being used to improve the oral delivery of PWSDs. The aim of this study was to investigate the effect of lipid-based formulation, Type IIIA-LC, on the solubilization patterns of PWSDs, namely, carvedilol and felodipine. Solubility studies, for both drugs, were performed with LBF dispersed in -1) dog intestinal fluid (DIF), and 2) water, to identify and compare the extent of solubility in different matrices, and in silico to identify interesting patterns with any correlations in experimental and computational data. Solubility studies showed that carvedilol had better solubility in LBF when compared to felodipine. Computational studies showed that both drugs solubilized in the colloid in both digested and undigested states. Effect of drug loading had no significant difference on the solubilization patterns of both drugs. The maximum drug loading done was for 100 molecules though there is the possibility of the colloid having a higher capacity. Digestion did not seem to have a significant effect on the distribution of both drugs. In vitro and in silico data were in qualitative agreement and therefore, this computational model can be further used to study the specific processes causing solubilization, improvement, and development of new LBFs.
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Synthesis of a polar conjugated polythiophene for 3D-printing of complex coacervatesHeimonen, Johanna January 2021 (has links)
The aim of this thesis was to synthesize a functionalized polar conjugated polythiophene that could be (3D-) printed into form-stable structures for bio-interfacing. The material design rationale aimed for a water-processable polymer that had the capability of electronic and ionic conduction, by using a thiophene backbone and oligoethylene side chains. Functionalization of the oligoethylene side chains with carboxylate groups created a polyanion, which allowed for a bio-inspired approach to combine printability and form-stability through formation of complex coacervates. The synthesis of the conjugated monomer and polymer was optimized to provide a more sustainable and material efficient synthesis route. Combined structural analysis with 1H-NMR, FT-IR and UV-vis revealed successful synthesis of the target polymer. Spectro electrochemistry revealed that the polymer was optically and electrochemically active in both the protected and deprotected form. The obtained material is processable from water, and initial tests revealed that crosslinking can be achieved through formation of acid dimers, ionic crosslinks with Ca2+ ions and complex coacervation with a polycation. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
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Stoffwechseluntersuchungen bei klinisch gesunden Kühen unter besonderer Berücksichtigung der wasser- und fettlöslichen Antioxidantien.Gieseler, Jörn 19 April 2011 (has links)
Zusammenfassung
Jörn Gieseler
Stoffwechseluntersuchungen bei klinisch gesunden Kühen unter besonderer Berücksichtigung der wasserlöslichen und fettlöslichen Antioxidantien.
Medizinische Tierklinik, Veterinärmedizinische Fakultät, Universität Leipzig.
Eingereicht im Oktober 2010.
97 Seiten; 25 Abbildungen; 11 Tabellen; 351 Literaturangaben;
Schlüsselwörter: Rind, Stoffwechsel, wasserlösliche Antioxidantien, lipidlösliche Antioxidantien.
Die Gesundheit und Leistung von Milchkühen sind an einen stabilen Stoffwechsel gebunden. Abweichungen in der Nährstoffversorgung, im Intermediärstoffwechsel sowie seitens der Umweltbedingungen wirken sich belastend auf den Stoffwechsel und damit auf die Gesundheit des betroffenen Organismus aus. Mit gezielten Untersuchungen, z.B. Blutuntersuchungen, kann kontrolliert werden, ob der Stoffwechsel physiologisch oder durch Imbalancen belastet oder gar gestört ist.
Ziel der Untersuchung war es, die Aktivität der Glutathionperoxidase sowie die Konzentrationen der wasser- und fettlöslichen Antioxidantien im Blut von klinisch gesunden Kühen zu ermitteln, in Stoffwechseluntersuchungen mit einzubeziehen sowie den Einfluss von Laktation und Jahreszeit auf die o.g. Parameter zu prüfen.
Versuchsanordnung: Insgesamt wurden bei 85 SB/HF-Kühen (7990 kg fettkorrigierte Milch/Jahr) folgende zwei Gruppen analysiert: Gruppe 1: Zur Kontrolle des Laktationsverlaufes wurden 10 Kühe zum Zeitpunkt der 4. - 5. Woche ante partum (ap), 1. Woche ap, 1 - 2 Wochen post partum (pp), 4 Wochen pp und 8 - 12 Wochen pp untersucht. Gruppe 2: Im Verlaufe eines Jahres wurden im Abstand von 6 Wochen jeweils 10 gesunde Kühe, die sich alle in der 2. - 4. Woche post partum (pp) befanden, untersucht. Stall- und Außentemperaturen wurden dabei berücksichtigt. Die Tiere der beiden Gruppen wurden nach der klinischen Untersuchung weiter chemisch auf folgende Parameter getestet: Glutathionperoxidase (GPX), wasserlöslichen Antioxidantien (ACW), fettlösliche Antioxidantien (ACL), ß-Hydroxybutyrat (BHB), Cholesterol (Chol), Bilirubin (Bili), Glutamat-Dehydrogenase (GLDH), Aspartat Amino Transferase (AST), Creatinkinase (CK), Albumin (Alb), Harnstoff (Hast), Calcium (Ca), anorganisches Phosphat (Pi) und Chlorid (Cl). Durch eine Rationsberechnung wurde die Fütterung in die Untersuchung mit einbezogen.
Ergebnisse: Die Ergebnisse der peripartalen Stoffwechseluntersuchungen zeigen einen Anstieg der wasserlöslichen Antioxidantien (ACW) bis zur 4. Woche pp (p < 0,05). Ab 8 Wochen pp sinken die Konzentrationen wieder ab. Im Gegensatz dazu zeigt die Glutathionperoxidase (GPX) ihre höchste Aktivität bei den Trockenstehern. Es folgt eine starke Abnahme der Aktivität bis zur 4. Woche pp (p < 0,05) und ein Anstieg ab der 8. Woche pp (p < 0,05). Die Korrelation zwischen der Konzentration der ACW und der Aktivität der GPX verhält sich signifikant negativ. Die höchsten Konzentrationen der ACL liegen im Zeitraum des Trockenstehens, die niedrigste Konzentration 1. Woche ap - 4. Woche pp (p < 0,05). Ab 8 - 12 Wochen pp steigen die Konzentrationen der ACL wieder an. Die Stoffwechselparameter Harnstoff, Bilirubin, Cholesterol und BHB unterliegen Schwankungen über den gesamten Laktationsverlauf. Die AST-Aktivität erreicht ihren Höchststand 1-2 Wochen pp und liegt nur in dieser Zeit außerhalb der Toleranzgrenze. Die Albumin- und Pi-Konzentrationen sowie die CK-Aktivitäten bleiben im Laktationsverlauf konstant. Die Cl-Konzentration liegt in der 1. - 12. Woche pp unterhalb der physiologischen Grenze.
Die Ergebnisse der Stoffwechseluntersuchungen im Jahresverlauf zeigen einen kontinuierlichen Anstieg der ACW von Februar an, mit Höchstwerten im April und August (p < 0,05). Danach erfolgt ein kontinuierlicher Abfall der Werte bis zum Dezember. Die GPX zeigt eine generelle Verminderung ihrer Aktivität von Februar bis August (p < 0,05), um dann im Oktober wieder anzusteigen. Ihre Höchstwerte liegen im Januar und Dezember. Die Aktivität der GPX und die Konzentrationen der ACW korrelieren sowohl im Jahresverlauf als auch im Laktationsverlauf signifikant negativ. Die Konzentrationen der ACL unterliegen im Jahresverlauf Schwankungen. Dennoch korrelieren sie mit den Konzentrationen der GPX signifikant positiv. Die Harnstoff- und BHB-Konzentrationen sowie die Aktivität der CK liegen im gesamten Jahresverlauf innerhalb der physiologischen Grenzen. Die CK-Aktivität erreicht, zusammen mit der Albuminkonzentration, ihre Höchstwerte im Mai. Die Albuminkonzentrationen unterliegen mit dem Bilirubin im Jahresverlauf relativen Schwankungen. Das Bilirubin hat seine niedrigste Konzentration im Dezember und Januar bzw. seine höchsten Konzentrationen im Juli und August. Die Aktivität der AST zeigt einen gleichmäßigen Anstieg in den Sommermonaten. Ihre niedrigsten Aktivitäten liegen im Dezember und Januar. Die Cholesterolkonzentration sowie die Aktivität der AP sinken im Sommer ab. Cholesterol hat seine höchsten Konzentrationen im Dezember und Januar.
Schlussfolgerung: Schwankungen von Stoffwechselparametern im Jahres- und Laktationsverlauf betreffen vor allem die Antioxidantien. Deshalb können sowohl die in dieser Arbeit untersuchten Antioxidantien, als auch die anderen Stoffwechselparameter zur Beobachtung und Diagnostik von Stoffwechselbelastungen rund um die Kalbung sowie im Jahresverlauf zur Herdenkontrolle herangezogen werden. Die Referenzbereiche betragen für die ACW 12 bis 142 µmol/l und für ACL 1 bis 45 µmol/l.
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Quantitative analysis of allergens in peanut varieties and assessment of effects of food processing on peanut allergensMeng, Shi 04 May 2018 (has links)
Peanut, a major allergenic food, has life-threatening potential and is difficult to be totally avoided due to its common use in processed foods. Thermal processing can influence the allergenic properties of peanuts. However, the kinetics of the reactions caused by thermal processing has not been characterized. In our study, kinetics of the commonly used thermal processing methods on a commercial peanut cultivar (Virginia) using five time intervals was conducted. Water-soluble and SDS-sample buffer soluble proteins were extracted sequentially, and analyzed by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and western-blot using human plasma containing IgE antibodies. The relationships between thermal processing (time) and log transformed water-soluble/total extractable major allergen content could be explained by a simple linear regression kinetic model for most of the processing methods (except high-pressure steaming). Among all the methods with optimal processing point, frying for 6 min had relatively lower IgE binding (linear epitopes) ratio may be due to the fact that this processing condition causing break down, cross-linking and aggregation of Ara h 2, and relatively lower solubility. Besides thermal processing, enzymatic processing also is considered to be an effective method in the allergenicity of peanuts. Eleven peanut lines (Coded MS-1~MS-11, MS-9 is the check and a common cultivar namely Valencia) were pre-screened from 122 peanut lines harvested in 2015 for allergen levels. These pre-screened lines were re-planted in 2016 for further analysis. One line, MS-7, was selected for lower Ara h 1 (8.5-9.5% of total protein) and Ara h 2 (4.2-6.6% of total protein) content in 2015 and 2016. Roasted MS-9 (check) peanut powders were used for enzymatic treatment for enzyme selection. A first order kinetic reaction model was conducted to describe the relationship between enzyme concentration (0-400AzU/g) and IgE-binding property reduction. Among eight food-grade enzymes, bromelain, papain and ficin hydrolysates had lower IgE-binding properties in terms of high IgE-binding property reducing rate (K, ≥ 0.4) and were selected for the following study. MS-7 (selected) & MS-9 (at level of 200AzU/g) hydrolyzed by three selected enzymes (200AzU/g) were used for IgE binding property comparison, TGase crosslinking and functional properties study. After hydrolyzed by the selected enzymes (200 AzU/g), the emulsion and foaming stabilities were decreased. Emulsion and foaming stabilities were increased in TGase (5U/g protein) crosslinked hydrolysates, which were even higher than soy protein isolate (SPI). The IgE-binding properties of TGase treated hydrolysates were similar to the hydrolysates without TGase treatment. MS-7 hydrolysates (with/without TGase) possessed less IgE-binding properties and similar functionality as compared with MS-9 hydrolysates.
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Spårning av vägsalt och vattenlösliga föroreningar med CVES och EM prospektering / Tracing Road Salt and Water-Soluble Pollutants with CVES and EM ProbingHolmberg, Alicia, Bethoon, Tania January 2022 (has links)
Vid utformning av väginfrastruktur borde trafikrelaterade utsläpp med ursprung från väg- och däckslitage samt halkbekämpning tas hänsyn till för att nå en verklig hållbar utveckling. Exempel på vägrelaterade utsläpp är aluminium, bly, koppar, kadmium, krom och zink. I Sverige sprids det omkring 200 000 - 230 000 ton salt per år på vägarna för att bekämpa halka under vinterhalvåret. Vattenlösliga föroreningar antas spridas till omkringliggande miljöer på samma sätt som vägsalt gör. Därmed syftar projektet till att observera den elektriska resistiviteten och konduktiviteten som vägsalt ger upphov till, för att spåra utbredningen av vägsaltet och andra vattenlösliga trafikrelaterade föroreningar, samt dess påverkan på närliggande miljöer. Mätmetoderna som användes var CVES som bidrog med resistivitetsvärden samt EM som bidrog med konduktivitetsvärden. Mätningarna utfördes vid tre tillfällen; kring Arningevägen, E18 samt Skålhamravägen. På grund av tekniska fel har dock färre resistivitetsmätningar gjorts vid E18 i jämförelse med de andra vägarna som undersöktes. Resultatet från och analys av mätningar från respektive mätmetod presenteras visuellt i figurer med hjälp av programmen Res2DInv, Voxler och Surfer. Från dessa figurer kan slutsatser kring föroreningars potentiella spridning dras. Samtliga mättillfällen visade att utbredningen av vägsalt, och därmed föroreningar, spårades till områden närmast vägkanten men även ner till grundvattnet. Ett antal felkällor och begränsningar har påverkat resultatet, exempelvis att metoderna som användes i detta arbete inte undersöker exakta mängder av föroreningar. Detta eftersom mätmetoderna som har används är indirekta metoder som syftar till att spåra vägsalt. Vägarnas storlek och trafikmängd har även vägts in och överläggs kring hur dessa påverkat resultaten. Det framkommer att ju mer trafikerad en väg är desto mer sprids vattenlösliga vägrelaterade föroreningar. Det diskuteras även om hur omkringliggande miljö kan påverkas samt vilka av Sveriges miljömål och de globala målen är av relevans och motverkas. / When planning road infrastructure, traffic-related emissions originating from road and tire wear, as well as anti-skid mitigations, should be taken into account in order to achieve real sustainable development. Examples of road-related emissions are aluminum, lead, copper, cadmium, chromium and zinc. In Sweden, around 200,000 - 230,000 tonnes of salt per year are spread on roads to prevent slippage during the winter. Water-soluble pollutants are assumed to spread to surrounding environments the same way as road salt does. Thus, the project aims to observe the electrical resistivity and conductivity that road salt gives rise to, in order to trace the distribution of road salt and other water-soluble traffic-related pollutants, as well as its impact on nearby environments. The measurement methods used were CVES which provided resistivity values and EM which provided conductivity values. The measurements were performed on three occasions; around Arningevägen, E18 and Skålhamravägen. Due to technical errors however, fewer resistivity measurements have been made at E18 in comparison with the other roads that were investigated. The results and analysis from each measurement method are presented visually in figures using the programs Res2DInv, Voxler and Surfer. From these figures, conclusions can be drawn about the potential spread of pollutants. All measurement occasions showed that the distribution of road salt, and thus pollution, was traced to areas closest to the roadside but also down to the groundwater. A number of sources of errors and limitations have affected the result, for example that the methods used do not examine exact amounts of pollutants. This is because the measurement methods that have been used are indirect methods that aim to detect road salt. The size and amount of traffic on the roads have also been weighed in and discussed as to how these have affected the results. It appears that the busier a road is, the more water-soluble road-related pollutants are spread. It is also discussed how the surrounding environment can be affected and which of Sweden's environmental goals and Sustainable Development Goals are relevant and counteracted.
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Inosine 5’- monophosphate derived umami flavor intensity of beef determination by electrochemistry and chromatographyTo, Kezia Virellia 09 August 2022 (has links) (PDF)
The umami sensation contributes to beef flavor and acceptability. Inosine 5’- monophosphate (IMP) was the most abundant nucleotide in meat known to impart umami taste which thus far had been overlooked in meat flavor studies. The objectives of this study were to determine the umami taste threshold of inosine 5'-monophosphate (IMP), the effects of spiking IMP on the sensory descriptive attributes of various USDA graded beef strip steaks, and to differentiate beef by IMP content using electrochemistry. USDA Prime, Choice, and Select steaks were spiked with 0.3 and 0.6 mM IMP and analyzed chemically and organoleptically. Liquid chromatography-mass spectrometry and descriptive sensory analysis showed no changes in IMP content and the perceived sensory attributes of steaks. The electrochemical approach successfully differentiated IMP concentrations in aqueous solutions when present at 0.5 mM or above and was able to recognize the presence of nucleotides in the meat extract.
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[pt] AVALIAÇÃO DOS NÍVEIS E DA COMPOSIÇÃO QUÍMICA DE MATERIAL PARTICULADO EM ÁREAS URBANAS PRÓXIMAS ÀS ARENAS DOS JOGOS OLÍMPICOS RIO 2016 / [en] LEVELS AND CHEMICAL COMPOSITION EVALUATION OF PARTICULATE MATTER IN URBAN AREAS NEAR THE ARENAS OF THE 2016 OLYMPIC GAMESELIZANNE PORTO DE SOUSA JUSTO 13 July 2020 (has links)
[pt] Este trabalho tem como finalidade determinar a concentração em massa, caracterizar quimicamente as espécies presentes e identificar as possíveis fontes das amostras de material particulado (MP10 e MP2,5) coletados em locais com (Gericinó, Lagoa e Copacabana) e sem (Botafogo) a influência dos Jogos
Olímpicos, no Rio de Janeiro. As amostras de MP foram disponibilizadas pelo Instituto Estadual do Ambiente (INEA) referente ao ano de 2016, sendo os meses de julho a setembro considerados como a temporada Olímpica. A caracterização química das amostras foi realizada por ICP-MS e Cromatografia de Íons (CI).
Durante a temporada Olímpica, em 2016, foram reduzidos cerca de 26 porcento de MP10, quando comparados aos anos anteriores na mesma época do ano, por outro lado, o MP2,5 não foi reduzido. De todos os íons solúveis em água analisados, as maiores concentrações foram obtidas para o NO3-, SO4 2- e Na positivo nas duas frações de MP. As altas concentrações dos íons NO3 - e SO4 2- sugerem a presença de fontes antropogênicas. A partir do cálculo de nss (non-sea salt) foi possível observar que os íons Ca2 positivo, K positivo e SO4 2- tiveram uma contribuição marinha baixa. Os metais Fe, Cu e Ti foram os majoritários em todas as amostras nas duas frações de MP, enquanto que elementos como Mn, Pb, V e Ni foram detectados como minoritários. Correlações acima de 0,90 foram observadas entre Ti-Mn e Ti-Fe, sugerindo emissões de ressuspensão do solo e fortes correlações entre V-Ni e VPb mostram a influencia veicular como principal fonte. Finalmente, foi possível observar que houve uma influência dos Jogos Olímpicos na concentração em massa e de algumas espécies no MP2,5, enquanto que no MP10 não foi observada qualquer correlação. / [en] The main aim of this work was to determine the mass concentration, chemically characterize the species present and identify the possible sources of samples of particulate matter (PM10 e PM2.5) collected at sites with (Gericinó, Lagoa e Copacabana) and without (Botafogo) the influence of the Olympic Games in Rio de Janeiro. The PM samples were obtained from the Instituto Estadual do Ambiente (INEA) relative to the year 2016. The Olympic seasons considered were July to September of 2016. The chemical characterization of the samples was performed by ICP-MS and ion chromatography (IC). PM10 during the Olympic period were reduced 26 percent, when compared to previous years at the same time of the year. On the other hand, PM2.5 was not reduced during the Olympic period. Of all the water-soluble ions analyzed, the highest concentrations were obtained for NO3-, SO42- and Na plus in both fractions of PM. High concentrations of NO3 - and SO4 2- suggest the presence of anthropogenic sources. From calculation of non-sea salt was possible to observe that Ca2 plus, K plus and SO4 2- had a low marine contribution. Fe, Cu and Ti were the majority metals of all samples in both fractions of PM, while Mn, Pb, V and Ni were detected as minorities. Correlations above 0.90 are observed between Ti-Mn and Ti-Fe, suggested soil resuspension emissions. Strong correlations coefficients between V-Ni and V-Pb show the vehicular influence as the main source. Finally, it was possible to observe an influence of the Olympic Games in mass concentration and
some species in PM2.5, while in PM10 no correlation was observed.
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