Dissertations / Theses on the topic 'Sodium bicarbonate'

The objective of this experiment was to evaluate the effects of free-choice intake of sodium bentonite and sodium bicarbonate on physiological and production parameters. Eight Jerseys and seventeen Holsteins (four fistulated) were randomly assigned to two groups to equalize stage of lactation, age and production history. Two diets were fed: diet 1 without added sodium bicarbonate and diet 2 with sodium bicarbonate added at 1.2% of dry matter. Each group followed a different diet regime: 1) diet 1 with no free-choice (D1-NFC), 2) diet 2 with no free-choice (D2-NFC), 3) diet 1 with free-choice (D1-WFC), and 4) diet 2 with free-choice (D2-WFC). Free-choice options of sodium bentonite and sodium bicarbonate were offered side by side in a covered feeder to breed groups. Diets were changed every 10 d to provide 8 periods with a repetition of each diet regime. All diets were adjusted to 17% ADF and 17% CP. There were no differences with either breed among diets for blood and fecal observations or milk protein. Urine specific gravity was lower in both breeds when sodium bicarbonate was force-fed. Holsteins force-fed sodium bicarbonate had greater intake and milk production than Holsteins not force-fed. In Jerseys, milk urea nitrogen (MUN) decreased when sodium bicarbonate was added to the TMR. During periods in which cows were allowed free-choice access to sodium bentonite and sodium bicarbonate, Jerseys had higher urine pH, fat-corrected milk, MUN, and dry matter intake (DMI), and Holsteins had higher milk fat percentages and fecal pH.
Master of Science

La société Solvay est le plus grand producteur de bicarbonate de sodium raffiné au monde. Le NaHCO3 est un des produits parmi les plus connus et utilisés. Sa production a lieu dans des colonnes à bulles de volumes très importants. La production du bicarbonate de sodium raffiné dans ces réacteurs peut se résumer par la réaction entre une solution saturée de carbonate de sodium (Na2CO3) et le CO2(gaz)

Cette production implique la connaissance et le contrôle des réacteurs de type triphasique. En effet dans ce procédé on met en jeu deux types de transferts entre un gaz et un liquide le CO2 et la solution de Na2CO3 et entre un liquide et un solide, NaHCO3 (liq) et NaHCO3 (solide)

Le but de ce travail est d’acquérir des informations concernant la cristallisation du NaHCO3 dans une colonne à bulles. L’étude de la cristallisation de ce produit se fait au travers des modèles des cinétiques de cristallisation :la vitesse de croissance G (m•s-1) et la vitesse de nucléation J (
Doctorat en Sciences de l'ingénieur
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Abstract:

Sodium bicarbonate is one of the major chemical compound used worldwide. We have studied the mechanisms presiding the crystallization of this product in order to identify the kinetic parameters.

To be assured of the relevancy of our experimental results, we developed new and accurate measurement techniques to follow the supersaturation and to characterize the crystal morphologies of NaHCO3 like density measurement and images analysis.

The systematic study of the mechanisms and the kinetic parameters of the crystallization of NaHCO3 has been conducted by the use of three different types of crystallizers conceived and built at the Department of Industrial Chemistry of ULB :a fluidized bed crystallizer, a classic MSMPR crystallizer and a bubble column. By this choice, we were able to thoroughly investigate the intrinsic phenomena occurring in the crystallization of NaHCO3 from the ideal condition to the conditions close to the industry.

A NaHCO3 solution is typically a three components equilibrium, NaHCO3, Na2CO3 and CO2, depending on temperature. Our developed method of density measurement allows to measure continuously the supersaturation, during the crystallization. This method permits to neglect complex side effects due to Na2CO3 or dissolved mineral impurities. Density measurements are quick, sensitive and reliable.

We have shown that the growth of sodium bicarbonate is widely controlled by a reaction step at 45°C (< 200 µm). A diffusion step controlled growth occurs however for large crystals (>300-425µm) which consume much less material than the small ones. We have shown that the secondary nucleation of NaHCO3 is principally dominated by the surface nucleation.

The shape of the crystals obtained experimentally is in agreement with the theory, and strongly related to the size of the crystals and to the presence of impurities.

Based on experience of NaHCO3 crystallization without introduction of impurity, we have demonstrated that Ca2+ and Mg2+ suppress crystallization kinetics.

In the end, we have taken a brief look at the precipitation of NaHCO3 by gaz-liquid reaction in a bubble column.

By a comparative and a fundamental approach, our experimental studies lead us to improve our understanding and the operational parameters of the NaHCO3 industrial refining process.

Key words: Industrial crystallization, Sodium bicarbonate, Density measurement, Fluidized bed, MSMPR, Bubble column, Crystal growth, Nucleation

Résumé:

Le bicarbonate de sodium (NaHCO3) est un produit chimique important sur le marché mondial. Nous avons étudier les mécanismes de la cristallisation de ce produit afin d'en déterminer les paramètres cinétiques.

Afin de garantir l'analyse la plus objective de ces phénomènes, nous avons développé des techniques de mesures originales pour la connaissance de la sursaturation et pour la caractérisation des cristaux de NaHCO3 par densimétrie et par analyse d’images.

L'étude systématique des cinétiques et des mécanismes de cristallisation du NaHCO3 a été réalisée au moyen de trois cristallisoirs de conception différente, développés et construits au laboratoire du Service de Chimie Industrielle de l'ULB: un cristallisoir à lit fluidisé, un cristallisoir à cuve agitée MSMPR et une colonne à bulles. Ce choix nous a permis d'approfondir notre connaissance des phénomènes intrinsèques de la cristallisation du NaHCO3 dans des conditions idéales et des conditions proches des procédés industriels.

Une solution de NaHCO3 est un système à l’équilibre à trois composantes, NaHCO3, Na2CO3 et CO2 fonction de la température. La mise au point de la méthode densimétrique a permis la mesure de la sursaturation en NaHCO3 en continu. Cette méthode permet de s’affranchir des complications introduites par la présence de Na2CO3 et des impuretés inorganiques en solution. Les mesures de masse volumique sont rapides, précises et sensibles.

Nous avons démontré que la croissance du bicarbonate de sodium est largement dominé par l'étape de réaction à 45°C (< 200 µm). L'étape de diffusion intervient cependant dans la croissance de grands cristaux (>300-425µm) qui ne sont toutefois pas les plus grands consommateurs de matière. Nous avons mis en évidence que le mécanisme de la germination secondaire du NaHCO3 est principalement une germination secondaire vraie.

La forme des cristaux obtenus est parfaitement en accord avec la théorie et dépend étroitement de la taille des cristaux mais également de la présence d'impuretés.

En se basant sur les expériences de cristallisation du NaHCO3 sans introduction d’impuretés, nous avons démontré les effets de ralentissement des cinétiques de cristallisation d'ions tels que Ca2+ et Mg2+ .

Nous avons enfin brièvement abordé la précipitation du NaHCO3 par réaction gaz-liquide dans une colonne à bulles.

Cette approche expérimentale, comparative et fondamentale a permis d'affiner notre compréhension et d’optimiser un procédé industriel de raffinage du bicarbonate de sodium.

Mots clés: Cristallisation industrielle, Bicarbonate de sodium, Densimétrie, Lit fluidisé, MSMPR, Colonne à bulles, Croissance des cristaux, Germination

Doctorat en sciences appliquées
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Master of Science
Department of Biomedical Sciences
Warren Beard
Reasons for performing study: Caecal acidosis is a central event in the metabolic cascade that occurs following grain overload. Buffering the caecal acidosis by enterally administered sodium bicarbonate may be beneficial to affected horses. Objectives: To determine the effect and duration of enterally administered sodium bicarbonate (NaHCO[subscript]3) on caecal pH in healthy horses. Study design: Prospective controlled study using normal horses with caecal cannulas Methods: 9 horses previously fitted with a caecal cannula. 6 horses received 1.0 g/kg bwt NaHCO[subscript]3 via nasogastric tube and 3 control horses were given 3 L of water via nasogastric tube. Clinical parameters, water consumption, venous blood gases, caecal pH, faecal pH and faecal water content were measured at 6 hour intervals over a 36 hour study period. Results: Horses that received enterally administered NaHCO[subscript]3 had a significantly increased caecal pH that lasted the duration of the study. Treated horses increased their water intake, developed metabolic alcalemia, significantly increased sodium concentrations and significantly decreased potassium concentrations. Conclusions and potential relevance: Enterally administered NaHCO[subscript]3 may be beneficial in buffering the caecal acidosis that occurs following an acute carbohydrate overload

Récemment, il y a une demande accrue pour des cristaux de bicarbonate de sodium de propriétés d'usage spécifiques. Dans l'étude présentée, la réaction de cristallisation du bicarbonate de sodium est abordée et s'effectue dans un milieu triphasique dans lequel interviennent de nombreux phénomènes tels que le transfert de matière, la nucléation et la croissance cristalline. L'objectif de ce travail est d'étudier l'impact des paramètres opératoires, des additifs et de la technologie du réacteur sur la cristallisation du bicarbonate de sodium afin d'obtenir des cristaux avec une taille importante et une masse volumique apparente non tassée élevée. Les essais réalisés dans un réacteur ouvert de type MSMPR (Mixed Suspension Mixed Product Removal) ont permis d'optimiser les conditions opératoires du procédé et ont montré que l'ajout de calcium par le biais d'une solution de chlorure de calcium dans le milieu réactionnel améliore sensiblement la morphologie des cristaux, réduit la vitesse de nucléation tout en influençant légèrement la vitesse de croissance cristalline. Lorsque du polystyrène sulfonate de sodium (NaPSS) est ajouté au chlorure de calcium, sont obtenus des cristaux encore plus compacts avec des surfaces plus lisses et des arêtes marquées. A contrario, l'utilisation d'additifs chelatant le calcium comme le citrate de calcium dégrade la qualité des cristaux de bicarbonate de sodium et est donc proscrite pour une utilisation industrielle car les étapes de filtration et de séchage sont plus difficiles. Enfin, le passage d'un réacteur MSMPR à un réacteur à lit fluidisé a conduit, dans des conditions opératoires identiques, à une amélioration notable de la qualité du produit fini en produisant des cristaux avec une morphologie relativement sphérique et une taille importante
Recently, there is an increased demand for sodium bicarbonate crystals with specific properties. In the present study, the crystallization reaction of sodium bicarbonate is performed in a three-phase medium in which many phenomena such as mass transfer, nucleation and crystal growth occurred. The objective of this work is to study the impact of operating parameters, additives and reactor technology on the crystallization of sodium bicarbonate in order to obtain crystals with important size and high bulk density. The experiments carried out in a MSMPR (Mixed Suspension Mixed Product Removal) reactor have shown that the addition of calcium through a calcium chloride solution in the reaction mixture improves the crystal morphology, reduces the nucleation rate and weakly influences the crystal growth rate. When a mixture of sodium polystyrene sulfonate (NaPSS) and calcium chloride is used, more compact crystals with smoother surfaces and marked edges are obtained. Conversely, the use of calcium chelating additives such as calcium citrate affects the quality of sodium bicarbonate crystals and thus is prohibited for industrial use because the filtration and drying steps are much more difficult. Finally, the transposition from a MSMPR reactor to a fluidized bed reactor allows, under the same operating conditions, a significant improvement of the solid quality by producing big spheroidal particles

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
Este trabalho apresenta os resultados da quantificação do dano em superfícies dentinárias de molares humanos após jateamento com bicarbonato de sódio. Após a seleção e preparação das amostras, as mesmas foram divididas em dois grupos experimentais (Grupo Controle e Grupo de Jateamento). Inicialmente, mediu-se a rugosidade e dureza local (microdureza) do Grupo Controle, adotadas como valores padrão. Em seqüência, as amostras do Grupo de Jateamento foram submetidas à diferentes condições de jateamento, variando-se os parâmetros granulometria das partículas de bicarbonato de sódio (60 e 200 mesh), vazão da mistura água-bicarbonato de sódio-ar (mínima e máxima) e tempo de instrumentação (15 e 30 segundos). Finalmente, mediu-se a rugosidade e microdureza da região da dentina, bem como a área de depressões superficiais formada pelo jateamento. Os resultados mostraram que todas as condições de jateamento provocaram danos na região da dentina, caracterizados por aumentos de rugosidade e dureza, bem como o aparecimento de cavidades nesta região. A vazão mínima da mistura água-bicarbonato de sódio-ar provocou maiores rugosidades e endurecimentos na região dentinária. Por outro lado, as maiores áreas de cavidades na mesma região foram criadas por partículas menores quando jateadas com vazão máxima da mistura água-bicarbonato de sódio-ar
This work presents the results concerning the damage quantification in human molar dentine surfaces after blasting with sodium bicarbonate. After selection and preparation, the samples were divided into two experimental groups (Control Group and Blasting Group). Initially, the roughness and local hardness (microhardness) of the Control Group were measured and adopted as standard values. In the sequence, the samples of the Blasting Group were subjected to different blasting conditions, making change in parameters as grain size of the sodium bicarbonate particles (60 and 200 mesh), water-sodium bicarbonate-air mixture outflowing (minimum and maximum) and instrumentation time (15 and 30 seconds). Finally, the roughness and the microhardness of the dentine region were measured, as well as the area of the surface depressions due to blasting. The results showed that all blasting conditions caused damages in the dentine region, characterized by an increase in roughness and microhardness, as well as the creation of cavities in this region. The minimum water-sodium bicarbonate-air mixture outflowing was associated with larger values of roughness and microhardness in the dentine region. On the other hand, larger areas of cavities in the same region were created by smaller particles of sodium bicarbonate when blasted with maximum water-sodium bicarbonate-air mixture outflowing.

The effects of different types and amounts of sodium bicarbonate (NBC) were evaluated during the processing of flour tortillas. Fat encapsulated NBC, BS199, BS195, BS193, BS180, BS184, HM50 and HM70, and different particle-sized, non-encapsulated NBC, grade 1, grade 2, grade 3 and Tortilla Blend TM, were tested at different levels and combinations. Longer shelf stable tortillas with lower opacity were obtained when the level of NBC decreased. Tortillas with higher opacity, diameter and volume were obtained using the correct types of NBC. Increased tortilla opacity, thickness and shelf stability were obtained using 3 g encapsulated NBC/kg compared to non-encapsulated NBC. Encapsulation of NBC enables a temperature-triggered leavening reaction during baking of tortillas. Combinations of different levels and ratios of fast- and slow-release NBC did not yield significant improvements in tortilla properties. Tetrasodium pyrophosphate (TSPP, 0.15%) was added to modify protein functionality in tortilla dough containing less NBC. Tortillas with improved opacity, thickness and shelf stability resulted using TSPP with 3 g Grade 1 NBC/kg but similar improvements were not seen with encapsulated NBC. The effects of TSPP with low levels of NBC and slow reacting leavening acids were tested. Slight improvements in opacity were observed with sodium aluminum phosphate (SALP) compared to sodium aluminum sulfate (SAS) using encapsulated and non-encapsulated NBC. Tortillas produced with these formulations have longer shelf stabilities with similar properties. This benefits the consumers. The manufacturing costs for ingredients are 1.2% less using 0.15% TSPP with 3 g non-encapsulated NBC/kg flour. The manufacturer gains not only by the reduced cost of ingredients but also by the increased ease of attaining target diameter of tortillas. This could also be accomplished by using less dough to form the tortilla.

Class of 2015 Abstract
Objectives: To determine if a change in the amount of sodium bicarbonate (NaHCO3) in 5 different IV solutions will help prevent phenytoin from falling out of solution (i.e. precipitating). Our working hypothesis is that the stability of the phenytoin solution will change with different IV solutions and will increase with increasing the amount of sodium bicarbonate. Methods: A constant amount of phenytoin injection solution was mixed with a constant amount of one IV solution per beaker. Different amounts of alkalizing agents were then added to each phenytoin and IV mixture. Precipitation of the mixtures was observed every 30 minutes for 4 hours, then again in 24 hours. Results: When different IV solutions were added to the phenytoin and alkalizing agent mixture , the pH of the mixture dropped from 10 to 9 independent of the amount of alkalizing agent present in the mixture. All phenytoin mixtures precipitated within 60 minutes; 0.9% NaCl and phenytoin mixture being the one with the most delayed precipitation. Conclusions: Based on the result of this experiment, we rejected both of our specific aim hypotheses. Our hypothesis is rejected because the stability of the phenytoin solution will not change by using different IV solutions or by changing the amount of sodium bicarbonate.

In this study, the stress corrosion behavior of 3.5%NiCrMoV and 1%CrMoV steels was investigated. Tests were conducted at 95°C in carbonate/bicarbonate and sodium hydroxide solutions. Results from slow strain rate tensile tests and fracture mechanics experiments were compared. A new, easily machinable, specimen geometry for fracture mechanics experiments was tested. The influence of pH, potential, microstructure and inclusions were studied. Stress corrosion cracking (SCC) was found with all three steels in the 3.5M NaOH solution at active, passive and transpassive potentials. In the 1M carbonate/ bicarbonate solutions, the 1%CrMoV steels showed very severe cracking only during slow strain rate experiments. No major difference in cracking behavior was found between a regular 3.5%NiCrMoV steel and a super clean 3.5%NiCrMoV steel with low Mn and Si content. In acidic CO₂/H₂O environments, crack tip blunting was observed due to strong dissolution processes.
Applied Science, Faculty of
Materials Engineering, Department of
Graduate

This thesis examined four key areas considered to contribute to why the efficacy of sodium bicarbonate (NaHCO3) as an ergogenic aid remains equivocal. Firstly, familiarisation to and test re-test reliability of continuous constant load cycling to exhaustion (TLIM) at 110% peak power output (WPEAK) were investigated. Results indicated two trials are required before participants become fully familiarised and reliable data are obtained and that daily biological variation was 6 ± 11% (16 ± 28 s). The primary aim of study two was to determine the most appropriate exercise intensity for future studies in this thesis. A secondary aim was to elucidate why certain participants appear to respond to NaHCO3 ingestion and others do not (Price and Simons 2010, Saunders et al. 2011). Therefore, we evaluated cycling TLIM at 100%, 110% and 120% WPEAK in the same participants. NaHCO3 ingestion increased TLIM by 17% compared to placebo (PLA) at 100% WPEAK. This was due, at least in part, to attenuated localised ratings of perceived exertion (RPEL). No difference in group level data was observed between treatments at 110% WPEAK or 120% WPEAK although there was marked inter and intra individual variance. Thirdly, in order to evaluate the efficacy of NaHCO3 at a tissue level we examined the effects of NaHCO3 on dynamic isolated muscle performance undergoing cyclical length changes. Acute power output (PO) was on average 7.0% greater for NaHCO3 treated extensor digitorum longus (EDL) muscles and 3.6% greater for NaHCO3 treated soleus (SOL) muscles compared to control (CON). Increases in PO were due to greater force production throughout shortening. Treatment of EDL and SOL did not alter the pattern of fatigue at a group level although similar to study 2 there was marked inter individual variation. Finally, to determine the effects of training status we evaluated the effects of 6 weeks high-intensity cycling training on the efficacy of NaHCO3. Overall, pre-training TLIM was 10% greater with NaHCO3 compared to PLA with a benefit to harm odds ratio of 571. Overall, post-training TLIM was 6% greater with NaHCO3 compared to PLA with a benefit to harm odds ratio of 17. Similar to studies 2 and 3 individual variation was observed. Based on daily biological variation for TLIM of 6% (as determined in study 1) and a recommended benefit to harm odds ratio threshold of > 66, NaHCO3 improved TLIM before training only. We concluded that 6 weeks high-intensity cycling training reduces the effectiveness of NaHCO3 in previously non-cycling trained males. The change in efficacy is likely due to, at least in part, training induced changes in intracellular buffering capacity. In summary, NaHCO3 is an effective ergogenic aid for TLIM cycling at 100% WPEAK in non-cycling trained males. This is due, at least in part, to attenuated localised ratings of perceived exertion (RPEL). In contrast, 6-weeks high-intensity cycling training reduces the efficacy of NaHCO3 for TLIM cycling at 100% WPEAK in previously non-cycling trained males. The change in efficacy is likely due to, at least in part, training induced changes in intracellular buffering capacity. At a skeletal muscle level, NaHCO3 increases acute PO in both predominantly fast (EDL) and predominantly slow (SOL) twitch muscle fibres, due to greater force production throughout shortening.

BACKGROUND:The glycolytic nature of malignant tumors contributes to high levels of extracellular acidity in the tumor microenvironment. Tumor acidity is a driving force in invasion and metastases. Recently, it has been shown that buffering of extracellular acidity through systemic administration of oral bicarbonate can inhibit the spread of metastases in a mouse model for metastatic breast cancer. While these findings are compelling, recent assessments into the use of oral bicarbonate as a cancer intervention reveal limitations.METHODS:We posited that safety and efficacy of bicarbonate could be enhanced by dichloroacetate (DCA), a drug that selectively targets tumor cells and reduces extracellular acidity through inhibition of glycolysis. Using our mouse model for metastatic breast cancer (MDA-MB-231), we designed an interventional survival study where tumor bearing mice received bicarbonate, DCA, or DCA-bicarbonate (DB) therapies chronically.RESULTS:Dichloroacetate alone or in combination with bicarbonate did not increase systemic alkalosis in mice. Survival was longest in mice administered bicarbonate-based therapies. Primary tumor re-occurrence after surgeries is associated with survival rates. Although DB therapy did not significantly enhance oral bicarbonate, we did observe reduced pulmonary lesion diameters in this cohort. The DCA monotherapy was not effective in reducing tumor size or metastases or improving survival time. We provide in vitro evidence to suggest this outcome may be a function of hypoxia in the tumor microenvironment.CONCLUSIONS:DB combination therapy did not appear to enhance the effect of chronic oral bicarbonate. The anti-tumor effect of DCA may be dependent on the cancer model. Our studies suggest DCA efficacy is unpredictable as a cancer therapy and further studies are necessary to determine the role of this agent in the tumor microenvironment.

Le bicarbonate de soude raffiné, produit industriellement par la société Solvay, est fabriqué dans des colonnes à bulles de grande taille, appelées les colonnes BIR.

Dans ces colonnes, une phase gazeuse contenant un mélange d’air et dioxyde de carbone (CO2) est dispersée sous forme de bulles dans une solution aqueuse de carbonate et de bicarbonate de sodium (respectivement Na2CO3 et NaHCO3). Cette dispersion donne lieu à un transfert de CO2 des bulles vers la phase liquide. Au sein des colonnes, la phase gazeuse se répartit dans deux populations de bulles :des petites bulles (diamètre de quelques mm) et des grandes bulles (diamètre de quelques cm). Le transfert bulle-liquide de CO2 est couplé à des réactions chimiques prenant place en phase liquide, qui conduisent à la conversion du Na2CO3 en NaHCO3. Une fois la concentration de saturation dépassée le NaHCO3 précipite sous forme de cristaux et un mélange liquide-solide est recueilli à la sortie de ces colonnes.

Ce travail, réalisé en collaboration avec la société Solvay, porte sur l’étude et la modélisation mathématique des phénomènes de transfert de matière entre phases, couplés à des réactions chimiques, prenant place au sein d’une colonne BIR. L’association d’études sur des colonnes à bulles à l’échelle industrielle ou réduite (pilote) et d’études plus fondamentales sur des dispositifs de laboratoire permet de développer une meilleure compréhension du fonctionnement des colonnes BIR et d’en construire un modèle mathématique détaillé.

L’objectif appliqué de ce travail est la mise au point d’un modèle mathématique complet et opérationnel d’une colonne BIR. Cet objectif est supporté par trois blocs de travail, dans lesquels différents outils sont développés et exploités.

Le premier bloc est consacré à la modélisation mathématique du transfert bulle-liquide de CO2 dans une solution aqueuse de NaHCO3 et de Na2CO3. Ce transfert est couplé à des réactions chimiques en phase liquide qui influencent sa vitesse. Dans un premier temps, des modèles sont développés selon des approches unidimensionnelles classiquement rencontrées dans la littérature. Ces approches passent par une idéalisation de l’écoulement du liquide autour des bulles. Une expression simplifiée de la vitesse du transfert bulle-liquide de CO2, est également développée et validée pour le modèle de colonne BIR.

Dans un second temps, une modélisation complète des phénomènes de transport (convection et diffusion), couplés à des réactions chimiques, est réalisée en suivant une approche bidimensionnelle axisymétrique. L’influence de la vitesse de réactions sur la vitesse de transfert est étudiée et les résultats des deux approches sont également comparés.

Le deuxième bloc est consacré à l’étude expérimentale du transfert gaz-liquide de CO2 dans des solutions aqueuses de NaHCO3 et de Na2CO3. A cette fin, un dispositif expérimental est développé et présenté. Du CO2 est mis en contact avec des solutions aqueuses de NaHCO3 et de Na2CO3 dans une cellule transparente. Les phénomènes provoqués en phase liquide par le transfert de CO2 sont observés à l’aide d’un interféromètre de Mach-Zehnder.

Les résultats expérimentaux sont comparés à des résultats de simulation obtenus avec un des modèles unidimensionnels développés dans le premier bloc. De cette comparaison, il apparaît qu’une mauvaise estimation de la valeur de certains paramètres physico-chimiques apparaissant dans les équations de ce modèle conduit à des écarts significatifs entre les grandeurs observées expérimentalement et les grandeurs estimées par simulation des équations du modèle.

C’est pourquoi une méthode d’estimation paramétrique est également développée afin d’identifier les valeurs numériques de ces paramètres physico-chimiques sur base des résultats expérimentaux. Ces dernières sont également discutées.

Dans le troisième bloc, nous apportons une contribution à l’étude des cinétiques de précipitation du NaHCO3 dans un cristallisoir à cuve agitée. Cette partie du travail est réalisée en collaboration avec Vanessa Gutierrez (du service Matières et Matériaux de l’ULB).

Nous contribuons à cette étude par le développement de trois outils :une table de calcul Excel permettant de synthétiser les résultats expérimentaux, un ensemble de simulations de l’écoulement au sein du cristallisoir par mécanique des fluides numérique et une nouvelle méthode d’extraction des cinétiques de précipitation du NaHCO3 à partir des résultats expérimentaux. Ces trois outils sont également utilisés de façon combinée pour estimer les influences de la fraction massique de solide et de l’agitation sur la cinétique de germination secondaire du NaHCO3.

Enfin, la synthèse de l’ensemble des résultats de ces études est réalisée. Le résultat final est le développement d’un modèle mathématique complet et opérationnel des colonnes BIR. Ce modèle est développé en suivant l’approche de modélisation en compartiments, développée au cours du travail de Benoît Haut. Ce modèle synthétise les trois blocs d’études réalisées dans ce travail, ainsi que les travaux d’Aurélie Larcy (du service Transferts, Interfaces et Procédés de l’ULB) et de Vanessa Gutierrez. Les équations modélisant les différents phénomènes sont présentées, ainsi que la méthode utilisée pour résoudre ces équations. Des simulations des équations du modèle sont réalisées et discutées. Les résultats de simulation sont également comparés à des mesures effectuées sur une colonne BIR. Un accord raisonnable est observé.

A l’issue de ce travail, nous disposons donc d’un modèle opérationnel de colonne BIR. Bien que ce modèle doive encore être optimisé et validé, il peut déjà être utilisé pour étudier l’effet des caractéristiques géométriques des colonnes BIR et des conditions appliquées à ces colonnes sur le comportement des simulations des équations du modèle et pour identifier des tendances.

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The refined sodium bicarbonate is produced by the Solvay company using large size bubble columns, called the BIR columns.

In these columns, a gaseous phase containing an air-carbon dioxyde mixture (CO2) is dispersed under the form of bubbles in an aqueous solution of sodium carbonate and sodium bicarbonate (Na2CO3 and NaHCO3, respectively). This dispersion leads to a CO2 transfer from the bubbles to the liquid phase. Inside these columns, the gaseous phase is distributed in two bubbles populations :small bubbles (a few mm of diameter) and large bubbles (a few cm of diameter).

The bubble-liquid CO2 transfer is coupled with chemical reactions taking places in the liquid phase that leads to the conversion of Na2CO3 to NaHCO3. When the solution is supersaturated in NaHCO3, the NaHCO3 precipitates under the form of crystals and a liquid-solid mixture is extracted at the outlet of the BIR columns.

This work, realized in collaboration with Solvay, aims to study and to model mathematically the mass transport phenomena between the phases, coupled with chemical reactions, taking places inside a BIR column. Study of bubble columns at the industrial and the pilot scale is combined to a more fundamental study at laboratory scale to improve the understanding of the BIR columns functioning and to develop a detailed mathematical modeling.

The applied objective of this work is to develop a complete and operational mathematical modeling of a BIR column. This objective is supported by three blocks of work. In each block, several tools are developed and used.

The first block is devoted to the mathematical modeling of the bubble-liquid CO2 transfer in an NaHCO3 and Na2CO3 aqueous solution. This transfer is coupled with chemical reactions in liquid phase, which affect the transfer rate.

In a first time, mathematical models are developed following the classical one-dimensional approaches of the literature. These approaches idealize the liquid flow around the bubbles. A simplified expression of the bubble-liquid CO2 transfer rate is equally developed and validated for the BIR column model.

In a second time, a complete modeling of the transport phenomena (convection and diffusion) coupled with chemical reactions is developed, following an axisymmetrical twodimensional approach. The chemical reaction rate influence on the bubble-liquid transfer rate is studied and the results of the two approaches are then compared.

The second block is devoted to the experimental study of the gas-liquid CO2 transfer to NaHCO3 and Na2CO3 aqueous solutions. An experimental set-up is developed and presented. CO2 is put in contact with NaHCO3 and Na2CO3 aqueous solutions in a transparent cell. The phenomena induced in liquid phase by the CO2 transfer are observed using a Mach-Zehnder interferometer.

The experimental results are compared to simulation results that are obtained using one of the one-dimensional model developed in the first block. From this comparison, it appears that a wrong estimation of some physico-chemical parameter values leads to significative differences between the experimentally observed quantities and those estimated by simulation of the model equations. Therefore, a parametric estimation method is developed in order to estimate those parameters numerical values from the experimental results. The found values are then discussed.

In the third block is presented a contribution to the NaHCO3 precipitation kinetic study in a stirred-tank crystallizer. This part of the work is realized in collaboration with Vanessa Gutierrez (Chemicals and Materials Department of ULB).

Three tools are developed :tables in Excel sheet to synthetize the experimental results, a set of simulations of the flow inside the crystallizer by Computational Fluid Dynamic (CFD) and a new method to extract the NaHCO3 precipitation kinetics from the experimental measurements. These three tools are combined to estimate the influences of the solid mass fraction and the flow on the NaHCO3 secondary nucleation rate.

Finally, the synthesis of all these results is realized. The final result is the development of a complete and operational mathematical model of BIR columns. This model is developed following the compartmental modeling approach, developed in the PhD thesis of Benoît Haut. This model synthetizes the three block of study realized in this work and the studies of Aurélie Larcy (Transfers, Interfaces and Processes Department of ULB) and those of Vanessa Gutierrez. The equations modeling the phenomena taking place in a BIR column are presented as the used method to solve these equations. The equations of the model are simulated and the results are discussed. The results are equally compared to experimental measurement realized on a BIR column. A reasonable agreement is observed.

At the end of this work, an operational model of a BIR column is thus developed. Although this model have to be optimized and validated, it can already be used to study the influences of the geometrical characteristics of the BIR columns and of the conditions applied to these columns on the behaviour of the model equation simulations and to identity tendencies.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Sete cães foram submetidos à anestesia inalatória com isoflurano para permitir a realização do bloqueio peribulbar, com punção única inferior, guiado por ultrassonografia com ropivacaína a 1%, e assim comprovar a eficácia desta técnica de bloqueio guiado na redução do volume anestésico injetado de ropivacaína a 1%, e avaliar possíveis efeitos potencializadores como a redução da latência e do volume anestésico utilizado, assim como complicações oftálmicas associadas à alcalinização do anestésico com bicarbonato de sódio a 0,33%. Foram avaliados dois volumes diferentes de ropivacaína a 1% (0,2 mL/Kg e 0,1 mL/Kg) associados ou não ao bicarbonato de sódio a 0,33% que, ao ser adicionado ao anestésico, elevou o pH da solução anestésica para 6,0. Uma vez realizado o bloqueio peribulbar, com punção única inferior, guiado por ultrassom o tempo necessário para ocorrer a centralização do bulbo do olho era cronometrado, e os animais permaneciam anestesiados para a aferição da pressão intraocular, que foi realizada imediatamente e 15 minutos após o bloqueio e, concluída essa mensuração, a anestesia foi encerrada. Com os cães já despertos foram avaliados os seguintes parâmetros: a pressão intraocular, o diâmetro pupilar, o bloqueio motor, sensitivo (realizado por meio de estesiometria corneal com estesiômetro de Cochet e Bonnet), e a observação das intercorrências oftálmicas como quemose, hiperemia conjuntival, hematoma subconjuntival, prurido e secreção ocular. As análises estatísticas foram conduzidas com o auxílio do software de livre acesso RStudio. Variáveis não paramétricas, ordinais e categóricas foram avaliadas por teste estatística tipo ANOVA ou ATS. Variáveis contínuas paramétricas foram avaliadas pelo Modelo linear misto para medidas repetidas. O Teste Kendall Tau-b foi utilizado para verificar possíveis correlações entre as variáveis. Com exceção do reflexo fotomotor (G0,1: 30 (0-90) e G0,2: 150 (0-210 minutos), não houve diferença significativa entre grupos quando comparado a latência, a pressão intraocular, o diâmetro pupilar, as durações e qualidade dos bloqueios motor e sensitivo, e as intercorrências oftálmicas, mas houve diferença significativa quando comparados os momentos dentro de um mesmo grupo para todas as variáveis analisadas. Deste modo concluiu-se que entre os volumes avaliados de ropivacaína a 1%, no bloqueio peribulbar guiado por US em cães, houve um melhor desempenho clínico relacionado a intensidade e duração dos bloqueios sensitivo e motor, com o volume de 0,2 mL/kg. A adição de NaHCO3 - a 0,33% não agregou benefícios, como a potencialização da ação ou redução da latência anestésica, contudo não ocorreram intercorrências oftálmicas significativas relacionadas diretamente à sua administração ou a da ropivacaína a 1%.
Seven dogs were subjected to inhalation anesthesia with isoflurane to allow the realization of peribulbar block, with lower single puncture, guided by ultrasound with 1% ropivacaine, and thus prove the effectiveness of this blocking technique guided in reducing anesthetic volume of ropivacaine 1%, and evaluate possible potentiating effects such as reducing the latency and anesthetic volume used and ophthalmic complications associated with the anesthetic alkalinization with sodium bicarbonate 0,33%. We evaluated two different volumes of 1% ropivacaine (0.2 ml / kg and 0.1 ml / kg) with or without sodium bicarbonate to 0.33% which when added to anesthetic raised the pH of the solution anesthetic to 6.0. Once performed peribulbar block, with lower single puncture guided by ultrasound time required to place the centralization of the eye bulb was timed, and the animals remained anesthetized for the measurement of intraocular pressure was carried out immediately and 15 minutes after blockade and completed this measurement, anesthesia was terminated. With dogs the following parameters already awake were evaluated intraocular pressure, pupil size, the duration and intensity of motor block, sensory (performed by esthesiometry corneal with esthesiometer Cochet and Bonnet), and observation of ophthalmic complications as chemosis, conjunctival hyperemia, subconjunctival hematoma, pruritus, and ocular secretion resulting from the anesthetic technique or employee drug. Statistical analyzes were conducted with the free software Rstudio. nonparametric variables, ordinal variables and categorical variables were evaluated using the statistical test ANOVA type or ATS. Parametric continuous variables were assessed by linear mixed model for repeated measures. The Test Kendall Tau-b was used to verify possible correlations between variables. Aside from fotomotor reflex (G0,1: 30 (0-90) and G0,2: 150 (0-210 minutes), there was no significant difference between groups when compared to latency, intraocular pressure, pupil size, the durations and quality of sensory and motor block, and ophthalmic complications, but there was significant difference when comparing times within the same group for all variables. Thus it was concluded that among the evaluated volumes of 1% ropivacaine in the lock US peribulbar guided in dogs, there was a better clinical performance related to the intensity and duration of sensory and motor block, with a volume of 0.2 ml / kg. the addition of 0.33% NaHCO3 no added benefits, such as potentiation of action or reduction of latency anesthetic, but no significant ophthalmic complications directly related to its administration or the 1% ropivacaine.
FAPESP: 2014/09654-6

Orientador: Valéria Nobre Leal de Souza Oliva
Banca: Paulo Sérgio Patto dos Santos
Banca: Alexandre Lima de Andrade
Banca:Antonio José de Araújo Aguiar
Banca: Verônica Batista de Albuquerque
Resumo:Sete cães foram submetidos à anestesia inalatória com isoflurano para permitir a realização do bloqueio peribulbar, com punção única inferior, guiado por ultrassonografia com ropivacaína a 1%, e assim comprovar a eficácia desta técnica de bloqueio guiado na redução do volume anestésico injetado de ropivacaína a 1%, e avaliar possíveis efeitos potencializadores como a redução da latência e do volume anestésico utilizado, assim como complicações oftálmicas associadas à alcalinização do anestésico com bicarbonato de sódio a 0,33%. Foram avaliados dois volumes diferentes de ropivacaína a 1% (0,2 mL/Kg e 0,1 mL/Kg) associados ou não ao bicarbonato de sódio a 0,33% que, ao ser adicionado ao anestésico, elevou o pH da solução anestésica para 6,0. Uma vez realizado o bloqueio peribulbar, com punção única inferior, guiado por ultrassom o tempo necessário para ocorrer a centralização do bulbo do olho era cronometrado, e os animais permaneciam anestesiados para a aferição da pressão intraocular, que foi realizada imediatamente e 15 minutos após o bloqueio e, concluída essa mensuração, a anestesia foi encerrada. Com os cães já despertos foram avaliados os seguintes parâmetros: a pressão intraocular, o diâmetro pupilar, o bloqueio motor, sensitivo (realizado por meio de estesiometria corneal com estesiômetro de Cochet e Bonnet), e a observação das intercorrências oftálmicas como quemose, hiperemia conjuntival, hematoma subconjuntival, prurido e secreção ocular. As análises estatísticas foram conduzidas com o auxílio do software de livre acesso RStudio . Variáveis não paramétricas, ordinais e categóricas foram avaliadas por teste estatística tipo ANOVA ou ATS. Variáveis contínuas paramétricas foram avaliadas pelo Modelo linear misto para medidas repetidas. O Teste Kendall Tau-b foi utilizado... (resumo completo clicar acesso eletronico abaixo)
Abstract: Seven dogs were subjected to inhalation anesthesia with isoflurane to allow the realization of peribulbar block, with lower single puncture, guided by ultrasound with 1% ropivacaine, and thus prove the effectiveness of this blocking technique guided in reducing anesthetic volume of ropivacaine 1%, and evaluate possible potentiating effects such as reducing the latency and anesthetic volume used and ophthalmic complications associated with the anesthetic alkalinization with sodium bicarbonate 0,33%. We evaluated two different volumes of 1% ropivacaine (0.2 ml / kg and 0.1 ml / kg) with or without sodium bicarbonate to 0.33% which when added to anesthetic raised the pH of the solution anesthetic to 6.0. Once performed peribulbar block, with lower single puncture guided by ultrasound time required to place the centralization of the eye bulb was timed, and the animals remained anesthetized for the measurement of intraocular pressure was carried out immediately and 15 minutes after blockade and completed this measurement, anesthesia was terminated. With dogs the following parameters already awake were evaluated intraocular pressure, pupil size, the duration and intensity of motor block, sensory (performed by esthesiometry corneal with esthesiometer Cochet and Bonnet), and observation of ophthalmic complications as chemosis, conjunctival hyperemia, subconjunctival hematoma, pruritus, and ocular secretion resulting from the anesthetic technique or employee drug. Statistical analyzes... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor

Abstract The Effects of a Combined Supplementation of Creatine and Sodium Bicarbonate on Repeated Sprint Performance James Jeremy Barber There is well-established research that suggests both creatine and sodium bicarbonate are effective ergogenic aids. However, only one published study has examined the combined effects of creatine and sodium bicarbonate. The primary purpose of this study was to determine if a combined supplementation of creatine monohydrate and sodium bicarbonate would further enhance the well-documented effects of creatine supplementation alone on repeated sprint performance. Thirteen healthy and fit males (Mean age = 21.15 ± 0.65 years and mean VO2 max = 66.72 ± 5.78) participated in this experimental study using a double-blinded crossover study design in which each subject was used as his own control. All subjects completed 3 conditions, followed by a 3-week washout period between each condition: 1) Placebo (Pl; 5 g maltodextrin + 0.5 g/kg maltodextrin), 2) Creatine (Cr; 5 g + 0.5 g/kg maltodextrin), and 3) Creatine plus sodium bicarbonate (Cr+Sb; 5g + 0.5 g/kg sodium bicarbonate). Each condition was a 2-day supplementation. In the morning after each supplementation, peak power, RPP, mean power, RMP, fatigue index, and perceptions of fatigue and GI distress were assessed during six 10-second repeated Wingate tests. Blood bicarbonate, pH, and lactate were measured 5 minutes before testing and immediately after the last Wingate sprint. The main findings were; 1) Cr+Sb produced 7% greater relative peak power and 4.6% greater peak power values than placebo, and 2) Cr+Sb demonstrated the greatest attenuation of decline in relative peak power over six repeated sprints. However, in contrast to our hypotheses, no benefits from either supplementation were observed for relative mean power, fatigue index, and perception of fatigue. Considering that this current study found benefits from combining creatine and sodium bicarbonate, it suggests that combining the supplements may improve repeated sprint performance. Future research on a greater sample size, a specific athletic population, various exercise modes, and comparing results with a sodium bicarbonate alone supplementation would be beneficial in determining if this combined supplementation is worthwhile.

Nesse estudo comparou-se o efeito tamponante do HEPES e Bicarbonato de Sódio em manter o pH e a viabilidade do sêmen resfriado de pôneis da raça Brasileira. As alterações no pH ocasionadas por diferentes diluições com diluente a base de leite desnatado em pó sem tampão a 5 e a 15°C também foram medidas. No experimento 1 avaliou-se o efeito da diluição e da temperatura de resfriamento sobre a motilidade, integridade de membrana, pH e atividade mitocondrial do sêmen pré e pós resfriamento. O sêmen de nove pôneis da raça Brasileira (dois ejaculados/pônei) foi diluído em diluente a base de leite desnatado (em pó) sem tampão e refrigerado a 5 ou 15°C por 48h em três diferentes diluições (1+1, 1+2, 1+3). As três diluições não alteraram os parâmetros avaliados após a diluição a fresco. A diluição 1+1 resultou em valores maiores de pH (7,63 e 7,57, respectivamente) e menor percentual de motilidade progressiva (MP) a 5 e a 15°C. O maior percentual de células íntegras (1+1=44,16; 1+2=48,16; 1+3=50,05) foi detectado a 15°C (P < 0,01), independente da diluição. A MP foi maior nas 48h de resfriamento (39,72%; P < 0,05) quando o sêmen foi diluído a 1+3 e refrigerado a 15°C. A atividade mitocondrial (P > 0,05) em função do tempo e temperatura foi similar entre as diluições. No experimento 2 avaliou-se o efeito tampão do bicarbonato de sódio e do HEPES em diluentes sobre a viabilidade de espermatozoides resfriados a 5°C durante 48h. Os diluentes testados compunham-se de leite desnatado em pó com bicarbonato de sódio (A), HEPES (B) ou diluente sem tampão (C). O sêmen de sete pôneis da raça Brasileira (três ejaculados/pônei) foi utilizado e a motilidade progressiva foi similar entre os diluentes (P > 0,05) após a diluição. Nas 24 e 48h, a MP foi, respectivamente, para A (44,76%; 25,23%), B (51,42%; 38,09%) e C (54,05%; 41,66%). A integridade da membrana plasmática foi similar após a exposição aos três diluentes. A fresco, a atividade mitocondrial foi maior (P < 0,05) no sêmen exposto ao diluente A (A=1,05nm, B=0,81nm, C=0,79nm) e após 24h A e B foram similares (0,83nm; 0,73nm), enquanto que no diluente C observou-se menor atividade (0,64nm). Nas 48h não houve diferença (A=0,72; B=0,69; C=0,63; P > 0,05). O pH do diluente e sua osmolaridade, assim como o pH do sêmen diluído foi maior no diluente A (8; 382; 7,9), intermediário (7,5; 362; 7,32) no B e menor no C (7,16; 350; 7,07). A peroxidação lipídica e a indução da peroxidação foram similares em todos os grupos. Sugere-se que, quando da utilização do sêmen a fresco, qualquer das diluições aqui testadas pode ser utilizada com segurança. O resfriamento do sêmen por 48h modifica e eleva o pH do sêmen. Os melhores resultados foram observados com o resfriamento do sêmen a 15°C por 48h e com a diluição 1+3 em um diluente a base de leite em pó desnatado sem tampão. O bicarbonato de sódio (A) reduz a MP e aumenta o pH do sêmen. O diluente sem tampão foi considerado o mais apropriado para uso imediato na IA. Tanto o diluente com HEPES, quanto o diluente sem tampão foram adequados para o resfriamento do sêmen equino a 5°C durante 48h.
This study compared the buffering effect of HEPES and sodium bicarbonate on pH and viability of Brazilian pony semen cooled at 5°C. pH changes caused by different dilutions using skim milk powder semen extender without buffer were also measured. In experiment 1, the effect of dilution and cooling temperature on semen motility, membrane integrity, mitochondrial activity and pH pre and post cooling was investigated. Ejaculates of nine Brazilian ponies (two ejaculates per pony) were diluted, of a non buffered powder milk extender and cooled at 5°C or 15°C during 48h in three different dilutions (1+1, 1+2 and 1+3). Dilutions did not change the parameters evaluated before cooling. Samples diluted 1+1 resulted in higher pH values (7.63 and 7.57, respectively) and lowest percentage of progressive motility (PM) at 5 and 15°C. All samples cooled at 15°C showed a lower incidence of abnormal spermatozoa (1+1 = 55.84%; 1+2 = 51.84%; 1+3 = 49.95%) (P < 0.01) independent of dilution. Progressive motility was higher when semen was cooled during 48h in 1+3 dilution at 15°C (39.72%; P < 0.05). Mitochondrial activity despite of time and temperature was similar (P > 0.05) among dilutions. In experiment 2, the buffer effect of sodium bicarbonate and HEPES on extenders were evaluated considering the maintenance of sperm viability after cooling at 5°C during 24 and 48h. A non-buffered milk powder extender (C = control) and the same extender buffered with Sodium Bicarbonate (A) and HEPES (B) was used. Semen from 7 Brazilian ponies (three ejaculates / pony) was used. Immediately after dilution sperm motility was evaluated and progressive motility was similar with all extenders (P > 0.05). At 24 and 48h after cooling at 5oC sperm motility was evaluated, respectively, on groups A (44.76%; 25.23%), B (51.42%; 38.09%) and C (54.05%; 41.66%). Plasma membrane integrity was similar after exposure to the three extenders. Before cooling, mitochondrial activity was higher (P <0.05) in extender A (A = 1.05nm, B = 0.81nm, C = 0.79nm). Mitochondrial activity after cooling for 24h was 0.83nm (A), 0.73nm (B) and 0.64nm (C). After 48h it decreased to 0.72nm (A), 0.69nm (B) and 0.63nm (C) (P > 0.05), respectively. The extenders pH, osmolarity and pH of diluted semen was higher in A (8; 382; 7.9), intermediate in B (7.5; 362; 7.32) and lower in C (7.16; 350; 7.07). Lipid peroxidation and its induction were similar in all groups. It was concluded that all dilution grades in fresh semen were adequate and that pH was affected and increased when semen was extended and cooled for 48h. The best results were observed when semen was diluted at 1+3 and cooled at 15°C for 48h in a non buffered powder milk extender. Sodium bicarbonate (A) reduces progressive motility and increases semen pH. The non buffered (C) semen extender was considered more appropriated for semen dilution for immediate use in artificial insemination. The non buffered and HEPES buffered semen extenders were considered appropriated for cooling equine semen at 5°C during 48h.

Release of uranium from Na-autunite, an artificial mineral created as a result of polyphosphate injection in the subsurface at the DOE Hanford Site, takes place during slow dissolution of the mineral structure. Stability information of the uranyl-phosphate phases is limited to conditions involving pH, temperature, and a few aqueous organic materials. The carbonate ion, which creates very strong complexes with uranium, is the predominant ion in the groundwater composition. The polyphosphate technology with the formation of autunite was identified as the most feasible remediation strategy to sequester uranium in contaminated groundwater and soil in situ. The objectives of the experimental work were (i) to quantify the effect of bicarbonate on the stability of synthetic sodium meta-autunite created as a result of uranium stabilization through polyphosphate injection, (ii) calculate the kinetic rate law parameters of the uranium release from Na-autunite during dissolution, and (iii) to compare the process parameters with those obtained for natural calcium meta-autunite. Experiments were conducted using SPTF apparatus, which consists of syringe pumps for controlling flow rate, Teflon reactors and a heating/cooling system. 0.25 grams of synthetic Na-autunite was placed in the reactor and buffer solutions with varying bicarbonate concentrations (0.0005 to 0.003 M) at different pH (6 - 11) were pumped through the reactors. Experiments were conducted at four different temperatures in the range of 5 - 60oC. It was concluded that the rate of release of uranium from synthetic Na-autunite is directly correlated to the bicarbonate concentration. The rate of release of uranium increased from 1.90 x 10-12 at pH 6 to 2.64 x 10-10 (mol m-2 s-1) at pH 11 at 23oC over the bicarbonate concentration range tested. The activation energy values were invariant with the change in the bicarbonate concentration; however, pH is shown to influence the activation energy values. Uranyl hydroxides and uranyl carbonates complexes helped accelerate the dissolution of autunite mineral.

Class of 2010 Abstract
OBJECTIVES: The purpose of this study was to determine the incidence of contrast induced nephropathy (CIN) for patients receiving a pre-hydration regimen to prevent CIN. METHODS: This was a descriptive retrospective chart review study. Charts were reviewed from Banner Boswell Medical Center and a nephrologist’s office in Sun City, Arizona. RESULTS: There were a total of 12 patients included in the study. The population after completetion of chart reviews consisted of 6 male patients and 6 female patients. The age range of the patients included was 54-90 years old. CIN occurred in zero of the twelve patients. Half of the 12 patients had a decrease in serum creatinine ranging from 0.1- 0.6 mg/dL, 24-48 hours post-diagnostic procedure. CONCLUSIONS: There was no incidence of CIN after the 12 patients received the specific protocol. This study demonstrates the potential for this regimen as a pre-hydration option for individuals undergoing procedures in which radiocontrast is necessitated. A prospective observational study with a larger sample size would be warranted to determine the safety and efficacy of the protocol and increase the validity of the results of this descriptive study.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The experiment was conducted to evaluate the effects of marination with alkaline solutions on sensory and physical characteristics of normal and PSE pork. In a commercial slaughterhouse was measured the pH of carcasses (n = 526) for 45 minutes after slaughter (pH45), classified them into PSE (pH45 <5.8) or normal (pH45  5.8). After 24 hours of chilling of carcasses, meat samples from the Longissimus dorsi muscle from 20 carcasses were collected and distributed in the treatments in a completely randomized design, in the 2x4 factorial arrangement, being two conditions (normal and PSE) and four solutions of marination (TC control without marination; TM1 sodium bicarbonate and sodium chloride solution (pH 8.02), TM2 sodium tripolyphosphate and sodium chloride solution (pH 10.34) and TM3 sodium bicarbonate, sodium tripolyphosphate and sodium chloride solution (pH 8.97). The samples were evaluated for pH, color (L * a * b *), purge loss (PP), exudate loss (PE), cooking loss (PPC), shear force (FC) and sensory attributes (tenderness, juiciness and flavor). There was no interaction between the condition of the meat and the marination solutions on these parameters. The PSE meat did not differ from normal meat as to final pH, however showed higher lightness, PP, PE, PPC and FC. The marination increased the pH of the meat, reduced the lightness, PE, PPC and FC and improved tenderness, juiciness and flavor. For most traits the best values were observed in meat marinated with a mixture of three salts (TM3), demonstrating the synergy between them. The marination with solutions containing chloride, bicarbonate, tripolyphosphate sodium was effective in improving the quality of pork, making PSE meat similar to normal fresh pork.
O experimento foi conduzido com o objetivo de avaliar os efeitos da marinação com soluções alcalinas sobre características físicas e sensoriais da carne suína normal e PSE. Em um abatedouro comercial aferiu-se o pH das carcaças (n = 526) aos 45 minutos após o abate (pH45), classificado-as em PSE (pH45<5,8) ou normais (pH455,8). Após 24 horas de resfriamento das carcaças, amostras de carne provenientes do músculo Longissimus dorsi de 20 carcaças foram coletadas e distribuídas nos tratamentos, em delineamento inteiramente casualizado, em arranjo fatorial 2x4, sendo duas condições (normal e PSE) e quatro soluções de marinação (TC controle sem marinação; TM1 solução de bicarbonato de sódio e NaCl (pH 8,02); TM2 solução de tripolifosfato de sódio e NaCl (pH 10,34) e TM3 solução de bicarbonato de sódio, tripolifosfato de sódio e NaCl (pH 8,97). As amostras foram avaliadas quanto ao pH, coloração (L*, a*, b*), perda por purga (PP), perda de exsudato (PE), perda de peso por cozimento (PPC), força de cisalhamento (FC) e atributos sensoriais (maciez, suculência e sabor). Não houve interação entre a condição da carne e os tratamentos de marinação para os parâmetros avaliados. Carnes PSE não diferiram de carnes normais quanto ao pH final, entretanto apresentaram maior luminosidade, PP, PE, PPC e FC. A marinação aumentou o pH da carne, reduziu a luminosidade, PE, PPC e FC e melhorou a maciez, suculência e sabor. Para a maioria das características avaliadas os melhores valores foram observados para carnes marinadas com a mistura dos três sais (TM3), evidenciando o sinergismo entre eles. A marinação com soluções contendo cloreto, bicarbonato e tripolifosfato de sódio foram eficientes em melhorar as características de qualidade da carne suína, tornando as carnes PSE semelhantes à carne normal in natura.

Este estudo in vitro avaliou a influência do tempo de aplicação do bicarbonato de sódio a 10% na qualidade da união de um sistema adesivo universal unido ao esmalte bovino clareado por meio de testes de resistência de união (microtração imediata e após 6 meses) e grau de conversão na interface adesiva (espectroscopia micro-Raman). Cento e dez blocos de esmalte bovino (4x4 mm) foram planificados e distribuídos aleatoriamente em 5 grupos: C: controle, sem clareamento; B: clareamento com peróxido de hidrogênio 35% (HP); BS3: clareamento com HP seguido de tratamento com a solução de bicarbonato de sódio 10% (BS) por 3 min; BS5: clareamento com HP seguido de tratamento com BS por 5 min; BS10: clareamento com HP seguido de tratamento com BS por 10 min. O HP foi aplicado duas vezes (20 minutos cada, com exceção do grupo C) e em seguida as restaurações adesivas foram realizadas. Após 24 horas, 20 espécimes de cada grupo foram seccionados em palitos (1x1 mm) e submetidos ao teste de resistência de união (imediato e após 6 meses) em máquina de ensaios universal com velocidade de 0,5 mm/min (n=10). Os dados foram analisados por ANOVA a dois critérios (p <0,05). As médias das análises imediata e após 6 meses foram: C: 26,77 / 25,32; B: 26,42 / 26,42; BS3: 23,95 / 22,98; BS5: 23,65 / 26,64; BS10: 23,42 / 29,30. Nenhum dos fatores testados apresentou significância: tratamento (p=0,349) e tempo (p=0,234), não havendo interação entre estes (p=0,198). Falhas adesivas foram predominantes nos dois períodos de avaliação. Para a análise do grau de conversão, após 24 horas da restauração, 2 espécimes de cada grupo foram seccionados em fatias de 1mm, sendo apenas 3 fatias selecionadas. Os seguintes parâmetros foram utilizados: excitação dos espécimes com laser de argônio operando a 538 nm, espectro obtido a uma resolução ~4cm-1, sob uma região de espectro entre 1580-1660cm-1, verificando a altura dos picos 1608cm-1 e 1637cm-1. Os dados foram analisados por ANOVA a um critério (p <0,05) e as médias do grau de conversão foram: C: 71,10%; B: 72,11%; BS3: 73,98%; BS5: 69,25%; BS10: 70,56%. O fator de estudo tratamento não apresentou significância estatística (p=0,808). A adesão no esmalte clareado parece não ter sido afetada negativamente quando restaurações adesivas foram feitas imediatamente após o clareamento, independente da aplicação ou não da substância antioxidante. Mais estudos que avaliem a adesão em esmalte clareado, principalmente no que diz respeito ao grau de conversão e aos diferentes tipos de sistemas adesivos universais se fazem necessários para fins comparativos e para que possamos indicar seguramente as restaurações imediatas (quando necessárias) na prática clínica.
The present in vitro study evaluated the influence of the application time of 10% sodium bicarbonate in the adhesion quality of a universal adhesive system bonded to bleached enamel through microtensile bond strength testing (immediate and after 6 months) and the degree conversion (micro-Raman spectroscopy). One hundred and ten bovine enamel blocks (4x4mm) were flattened and randomly allocated into 5 groups: C: control, without bleaching; B: bleached with 35% hydrogen peroxide (HP); BS3: bleached and treated with 10% sodium bicarbonate solution (BS) for 3 min; BS5: bleached and treated with BS for 5 min; BS10: bleached and treated with BS for 10 min. HP was applied twice (20 minutes each, except in group C) and the adhesive restorations were performed. After 24 hours, 20 specimens from each group were sectioned into sticks (1x1 mm) and submitted to microtensile bond strength testing (immediately and after 6 months) in a universal testing machine with a crosshead speed of 0.5 mm/min (n = 10). Data was analyzed by two-way ANOVA (p <0.05). The means of the immediate and 6 months analysis were: C 26.77 / 25.32; B: 26.42 / 26.42; BS3: 23.95 / 22.98; BS5: 23.65 / 26.64; BS10: 23.42 / 29.30. None of the tested factors showed significance: treatment (p = 0.349) and time (p = 0.234), with no interaction between them (p = 0.198). Adhesive failures were predominant in both evaluation periods. For the degree of conversion analysis, 2 specimens of each group were sectioned into 1 mm slices after 24 hours of the restorative procedure, and 3 slices were selected. The following parameters were used: excitation of specimens with argon laser operating at 538 nm, spectrum obtained at a resolution of ~4cm-1, under a spectrum region between 1580-1660cm-1, evaluating the height of the peaks at 1608cm-1 and 1637cm-1. Data was analyzed by one-way ANOVA (p <0.05). The means of degree of conversion were: C: 71.10%; B: 72.11%; BS3: 73.98%; BS5: 69.25%; BS10: 70.56%. The study factor \"treatment\" was not statistically significant (p = 0.808). The results of bonding to bleached enamel was not negatively affected when adhesive restorations were made immediately after bleaching, regardless of the application of the antioxidant substance. Further studies to evaluate the adhesion on bleached enamel, mainly with regard to the degree of conversion and different types of universal adhesive systems are needed for comparative purposes. Only after this, the immediate restoration (if necessary) in clinical practice can be safely and indicated.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Com o objetivo de avaliar os efeitos dos nÃveis de sÃdio da raÃÃo nas fases de crescimento e de postura de codornas japonesas foram realizados dois experimentos, nos quais, foram avaliados os nÃveis de 0,07; 0,12; 0,17; 0,22; 0,27 e 0,32% de sÃdio. No primeiro experimento (fase de crescimento), 480 codornas com um dia de idade, foram distribuÃdas em um delineamento inteiramente casualizado, com seis tratamentos de oito repetiÃÃes de dez aves cada. Conforme os resultados, no perÃodo de 1 a 21 dias, houve aumento linear do consumo de raÃÃo e Ãgua com aumento dos nÃveis de sÃdio e efeito quadrÃtico no ganho de peso e conversÃo alimentar com nÃveis Ãtimos de 0,23% e 0,21% de sÃdio, respectivamente. De 21 a 42 dias, houve reduÃÃo linear no ganho de peso, aumento linear no consumo de Ãgua e prejuÃzo na conversÃo alimentar com o acrÃscimo de sÃdio na raÃÃo, enquanto, o consumo de raÃÃo nÃo foi influenciado. No perÃodo total (1 a 42 dias de idade) com o aumento de sÃdio na raÃÃo, observou-se aumento linear no consumo de Ãgua e na umidade das excretas e efeito quadrÃtico sobre a digestibilidade da matÃria seca (CDMS), nitrogÃnio (CDN), energia bruta (CDEB) e valores energia metabolizÃvel aparente (EMA) e aparente corrigida (EMAn) com nÃveis Ãtimos estimados de 0,20% para CDMS, 0,27% para o CDN e 0,19% para CDEB, EMA e EMAn. Ainda, nesse ensaio, observou-se que o desempenho da fase de postura nÃo foi influenciado significativamente pelo nÃvel de sÃdio recebido pelas codornas na fase de crescimento. No segundo experimento, 288 codornas com 16 semanas de idade foram distribuÃdas ao acaso em seis tratamentos com oito repetiÃÃes de seis aves por unidade experimental. Houve aumento linear do consumo de raÃÃo, consumo de Ãgua e peso do ovo com o acrÃscimo de sÃdio e efeito quadrÃtico para produÃÃo de ovos, massa de ovo e conversÃo alimentar com nÃveis Ãtimos de 0,23%, 0,24% e 0,23% de sÃdio, respectivamente. TambÃm, houve efeito quadrÃtico dos nÃveis de sÃdio para as percentagens de gema, casca e albÃmen, obtendo-se mÃxima proporÃÃo de albÃmen e casca e mÃnima de gema com 0,21% de sÃdio. NÃo houve efeito significativo dos nÃveis de sÃdio para Unidades Haugh, entretanto houve feito quadrÃtico para gravidade especÃfica, com nÃvel Ãtimo de 0,22% de sÃdio. O acrÃscimo de sÃdio nÃo afetou a umidade das excretas, mas houve efeito quadrÃtico sobre a digestibilidade da matÃria seca (CDMS), nitrogÃnio (CDN), energia bruta (CDEB) e valores energia metabolizÃvel aparente (EMA) e aparente corrigida (EMAn) com nÃveis Ãtimos estimados de 0,24% para CDMS, 0,22% para CDN, 0,21% para CDEB e 0,18% para EMA e EMAn. Considerando os resultados, pode-se recomendar que as raÃÃes para codornas japonesas na fase de crescimento (1 a 42 dias) sejam formuladas com nÃveis de sÃdio entre 0,12% e 0,23% e na fase de produÃÃo, com nÃveis entre 0,18% e 0,23% de sÃdio
With the aim to evaluate the effects of the sodium levels in the growth and laying phases of Japanese quails, we conducted two experiments in which we evaluated the sodium levels of de 0,07%; 0,12%; 0,17%; 0,22%; 0,27% and 0,32%. In the first experiment (growth phase), 480 quails with one day were distributed in a completely randomized design with six treatments of eight replications of ten birds each. According to the results, in the period from 1 to 21 days, there was a linear increase in feed and water intake with the increase in sodium levels and a quadratic effect in the weight gain and feed conversion with optimum sodium levels of 0,23% and 0,21%, respectively. In the period from 21 to 42 days, there was a linear reduction in the weight gain, linear increase in water intake and worse in feed conversion with the increase in sodium in the ration, while feed intake was not affected. In the total period (1 to 42 days of age) with the increase in sodium in the ration, we observed a linear increase in the water intake and in the excreta moisture and a quadratic effect on the digestibility of the dry matter (DCMS), nitrogen (CDN), gross energy (DCEB) and values of apparent metabolizable energy (AME) and apparent corrected (AMEn) with estimated optimum levels of 0,20% for DCMS, 0,27% for CDN and 0,19% for DCEB, AME and AMEn. Moreover, in this experiment we observed that the performance of the laying phase was not influenced significantly by the sodium level supplied to quails in the growth phase. In the second experiment, 288 quails with 16 weeks of age were distributed at random in six treatments with eight replications of six birds each. There was a linear increase in feed intake, in water intake, and in egg weight with the increase in sodium levels and a quadratic effect for egg production, egg mass and feed conversion with optimum sodium levels of 0,23%, 0,24% and 0,23%, respectively. Also, there was a quadratic effect of the sodium levels for percentages the yolk, shell and albumen, obtaining a maximum proportion of albumen and shell and a minimum proportion of yolk with a 0,21% sodium level. There was no significant effect of the sodium levels for the Haugh Units. However, there was a quadratic for specific gravity, with an optimum sodium level of 0.22%. The increase in sodium content did not affect the excreta moisture, but there was a quadratic effect on the digestibility of dry matter (DCMS), nitrogen (CDN), gross energy (DCEB) and values of apparent metabolizable energy (AME) and apparent corrected (AMEn) with estimated optimum levels of 0,24% for CDMS, 0,22% for CDN, 0,21% for CDEB and 0,18% for AME and AMEn. Considering the results, we can recommend that the diets for Japanese quails in the growth phase (1 to 42 days) are formulated with sodium levels between 0,12% and 0,23% and in the production phase with sodium levels between 0,18% and 0,23%

LIMA, Raffaella Castro. Níveis de sódio para codornas japonesas (Coturnix xotunix japonica) nas fases de crecimento e postura. 2009. 92 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Zootecnia, Programa de Pós-Graduação em Zootecnia, Fortaleza-CE, 2009.
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With the aim to evaluate the effects of the sodium levels in the growth and laying phases of Japanese quails, we conducted two experiments in which we evaluated the sodium levels of de 0,07%; 0,12%; 0,17%; 0,22%; 0,27% and 0,32%. In the first experiment (growth phase), 480 quails with one day were distributed in a completely randomized design with six treatments of eight replications of ten birds each. According to the results, in the period from 1 to 21 days, there was a linear increase in feed and water intake with the increase in sodium levels and a quadratic effect in the weight gain and feed conversion with optimum sodium levels of 0,23% and 0,21%, respectively. In the period from 21 to 42 days, there was a linear reduction in the weight gain, linear increase in water intake and worse in feed conversion with the increase in sodium in the ration, while feed intake was not affected. In the total period (1 to 42 days of age) with the increase in sodium in the ration, we observed a linear increase in the water intake and in the excreta moisture and a quadratic effect on the digestibility of the dry matter (DCMS), nitrogen (CDN), gross energy (DCEB) and values of apparent metabolizable energy (AME) and apparent corrected (AMEn) with estimated optimum levels of 0,20% for DCMS, 0,27% for CDN and 0,19% for DCEB, AME and AMEn. Moreover, in this experiment we observed that the performance of the laying phase was not influenced significantly by the sodium level supplied to quails in the growth phase. In the second experiment, 288 quails with 16 weeks of age were distributed at random in six treatments with eight replications of six birds each. There was a linear increase in feed intake, in water intake, and in egg weight with the increase in sodium levels and a quadratic effect for egg production, egg mass and feed conversion with optimum sodium levels of 0,23%, 0,24% and 0,23%, respectively. Also, there was a quadratic effect of the sodium levels for percentages the yolk, shell and albumen, obtaining a maximum proportion of albumen and shell and a minimum proportion of yolk with a 0,21% sodium level. There was no significant effect of the sodium levels for the Haugh Units. However, there was a quadratic for specific gravity, with an optimum sodium level of 0.22%. The increase in sodium content did not affect the excreta moisture, but there was a quadratic effect on the digestibility of dry matter (DCMS), nitrogen (CDN), gross energy (DCEB) and values of apparent metabolizable energy (AME) and apparent corrected (AMEn) with estimated optimum levels of 0,24% for CDMS, 0,22% for CDN, 0,21% for CDEB and 0,18% for AME and AMEn. Considering the results, we can recommend that the diets for Japanese quails in the growth phase (1 to 42 days) are formulated with sodium levels between 0,12% and 0,23% and in the production phase with sodium levels between 0,18% and 0,23%
Com o objetivo de avaliar os efeitos dos níveis de sódio da ração nas fases de crescimento e de postura de codornas japonesas foram realizados dois experimentos, nos quais, foram avaliados os níveis de 0,07; 0,12; 0,17; 0,22; 0,27 e 0,32% de sódio. No primeiro experimento (fase de crescimento), 480 codornas com um dia de idade, foram distribuídas em um delineamento inteiramente casualizado, com seis tratamentos de oito repetições de dez aves cada. Conforme os resultados, no período de 1 a 21 dias, houve aumento linear do consumo de ração e água com aumento dos níveis de sódio e efeito quadrático no ganho de peso e conversão alimentar com níveis ótimos de 0,23% e 0,21% de sódio, respectivamente. De 21 a 42 dias, houve redução linear no ganho de peso, aumento linear no consumo de água e prejuízo na conversão alimentar com o acréscimo de sódio na ração, enquanto, o consumo de ração não foi influenciado. No período total (1 a 42 dias de idade) com o aumento de sódio na ração, observou-se aumento linear no consumo de água e na umidade das excretas e efeito quadrático sobre a digestibilidade da matéria seca (CDMS), nitrogênio (CDN), energia bruta (CDEB) e valores energia metabolizável aparente (EMA) e aparente corrigida (EMAn) com níveis ótimos estimados de 0,20% para CDMS, 0,27% para o CDN e 0,19% para CDEB, EMA e EMAn. Ainda, nesse ensaio, observou-se que o desempenho da fase de postura não foi influenciado significativamente pelo nível de sódio recebido pelas codornas na fase de crescimento. No segundo experimento, 288 codornas com 16 semanas de idade foram distribuídas ao acaso em seis tratamentos com oito repetições de seis aves por unidade experimental. Houve aumento linear do consumo de ração, consumo de água e peso do ovo com o acréscimo de sódio e efeito quadrático para produção de ovos, massa de ovo e conversão alimentar com níveis ótimos de 0,23%, 0,24% e 0,23% de sódio, respectivamente. Também, houve efeito quadrático dos níveis de sódio para as percentagens de gema, casca e albúmen, obtendo-se máxima proporção de albúmen e casca e mínima de gema com 0,21% de sódio. Não houve efeito significativo dos níveis de sódio para Unidades Haugh, entretanto houve feito quadrático para gravidade específica, com nível ótimo de 0,22% de sódio. O acréscimo de sódio não afetou a umidade das excretas, mas houve efeito quadrático sobre a digestibilidade da matéria seca (CDMS), nitrogênio (CDN), energia bruta (CDEB) e valores energia metabolizável aparente (EMA) e aparente corrigida (EMAn) com níveis ótimos estimados de 0,24% para CDMS, 0,22% para CDN, 0,21% para CDEB e 0,18% para EMA e EMAn. Considerando os resultados, pode-se recomendar que as rações para codornas japonesas na fase de crescimento (1 a 42 dias) sejam formuladas com níveis de sódio entre 0,12% e 0,23% e na fase de produção, com níveis entre 0,18% e 0,23% de sódio

Sodium bicarbonate (NaHCO3) is a pre-exercise alkalotic buffering agent that is ingested to alleviate accumulation of hydrogen anions during exercise. As such, this supplement has been extensively used in scientific literature to assess NaHCO3 ergogenic properties during high intensity exercise. These ergogenic properties are likely to be apparent when exercise perturbs the acid-base balance with excessive H+ accumulation; therefore, the lowest intensity at which NaHCO3 may exert an ergogenic effect is during exercise performed within the severe intensity domain. The physiological characteristics of severe intensity exercise include exacerbated rise in [bla], and therefore acid-base perturbations, until the termination of exercise. The environmental conditions can also have an additive physiological stress to exercise; indeed, acute hypoxia increases the relative energy contribution of anaerobic glycolysis. The resultant effect is an exacerbated rise in H+ during exercise, which may, at least in part, contribute to the ergolytic effect of acute hypoxia on exercise performance and capacity. As such, severe intensity exercise performed in acute hypoxic conditions may benefit from NaHCO3 ingestion to alleviate acidic stress and mitigate for the ergolytic effect of acute hypoxia. The purpose of this thesis was to evaluate the effect of NaHCO3 on severe intensity exercise performed in acute hypoxic conditions. Furthermore, this effect was evaluated through the parameter of the powerduration relationship (i.e. CP and W') during all-out, intermittent and constant load exercise to exhaustion. Together, this series of investigations are the first to demonstrate that NaHCO3 may be an effective ergogenic aid in acute moderate hypoxic conditions. In particular, this effect was observed during exercise in the severe intensity domain, with NaHCO3 enhancing the capacity of W' during all-out and constant load exercise; along with increasing volume of work that can be performed at this intensity during intermittent exercise. Indeed, Chapter six demonstrated that NaHCO3 may accelerate the rate of recovery during intermittent exercise when applied to the W'_bal model. Interestingly, this thesis is the first to identify the presence of an intensity dependant effect, with the magnitude of NaHCO3 ergogenicity diminishing as exercise intensity rises from the severe intensity domain to supra-maximal intensities. Further research should consider testing these hypotheses in alternative ambient conditions to determine the efficacy of NaHCO3 (e.g. in normoxic conditions or in combined extreme environmental conditions).

Forty-eight Holstein cows at Utah State Dairy Farm were blocked statistically according to date of calving, previous milk production, and numbers of lactation at parturition. The cattle were assigned randomly to one of four treatments within blocks. The four treatments included a base ration (control, treatment #1), base ration plus .8% of sodium bicarbonate (treatment #2), base ration plus .4% of magnesium oxide (treatment #3), and base ration plus both .8% of sodium bicarbonate and .4% of magnesium oxide (treatment #4). The research was conducted from February 1983 to November 1984. A formagraph was used to measure milk coagulation parameters and pH was determined. There was no significant difference in milk coagulation parameters or pH between the control and the buffer treatments. Milk parameters were significantly different in individual cow, week, and milk pH. Milk parameters did not appear to be dependent upon season. Curd firmness was significant in interaction of season and treatment. Significant variations in milk pH were observed in relation to week, season, and individual cow. Overall treatments, the clotting time, K20, and pH value increased each week, and A30 decreased each week. The milk parameters and pH in each treatment were significant between weeks except K20 and A30 in treatment #3, and A30 in treatment #2 (p>0.05). The clotting time and K20 were negatively correlated with firmness, and there was positive correlation between Ct and K20 as expected. Somatic cell count was positively correlated with clotting time, K20, and pH and negatively correlated with A30. Milk pH was the most significant and had positive correlation coefficient with clotting time and firming rate and negative correlation coefficient with curd firmness.

Forty-eight Holstein cows at Utah State Dairy Farm were blocked statistically according to date of calving, previous milk production, and numbers of lactation at parturition. The cattle were assigned randomly to one of four treatments within blocks. The four treatments included a base ration (control, treatment #1), base ration plus .8% of sodium bicarbonate (treatment #2), base ration plus .4% of magnesium oxide (treatment #3), and base ration plus both .8% of sodium bicarbonate and .4% of magnesium oxide (treatment #4). The research was conducted from February 1983 to November 1984. A formagraph was used to measure milk coagulation parameters and pH was determined. There was no significant difference in milk coagulation parameters or pH between the control and the buffer treatments. Milk parameters were significantly different in individual cow, week, and milk pH. Milk parameters did not appear to be dependent upon season. Curd firmness was significant in interaction of season and treatment. Significant variations in milk pH were observed in relation to week, season, and individual cow. Overall treatments, the clotting time, K20, and pH value increased each wee, and A30 decreased each week. The milk parameters and pH in each treatment were significant between weeks except K20 and A30 in treatment #3, and A30 in treatment #2 (p Somatic cell count was positively correlated with clotting time, K20, and pH and negatively correlated with A30. Milk pH was the most significant and had positive correlation coefficient with clotting time and firming rate and negative correlation coefficient with curd firmness.

Short-term (3-7 days), high doses of creatine (20g/d) and/or sodium bicarbonate (0.5g/kg body weight) supplementation increase exercise performance during short term high intensity activities; however, it remains unclear whether long-term, low doses of these supplements have a positive impact on exercise performance. The purpose of this study was to determine the effects of long-term (8 weeks), low dose creatine supplementation on exercise performance, and whether combining creatine and sodium bicarbonate supplementation has an additive effect. Sixty-three healthy, habitually active, adults (28 M, 35 W; 22+2 years; 23+ 3 BMI) were randomly assigned by sex to one of three supplement groups: placebo (PL), creatine only (3g/day; Cr), or creatine plus sodium bicarbonate (3g creatine plus 1g sodium bicarbonate; Cr+Sb) for 8 weeks. Before and after supplementation subjects completed two exercise performance tests on separate days. Subjects completed repeated Wingate sprint tests (6 x 10 second sprints) and changes in the slope across the 6 sprints (rate of decline) was analyzed between groups. We also collected 5 km time-trial and the data were analyzed using repeated measures ANOVA. In the repeated sprint test, peak power output slope was significantly decreased (P=0.04) in PL (-83%) and Cr+Sb (-82%) but did not change in Cr alone and was significantly better (P=0.03) than Pl and Cr+Sb. Similarly, mean power output slope significantly decreased (P0.05) in time to completion. However, Cr alone significantly improved time to completion (-3%; P=0.01). Taken together, these data suggest that long-term, low dose creatine supplementation increases exercise performance but adding sodium bicarbonate supplementation has no beneficial impact on exercise performance.

Introduction: The exact causes of Exercise Induced Arterial Hypoxemia (EIAH) are not yet known. Earlier studies on the ergogenic effects of NaHCO3 have neglected to investigate the occurrence of EIAH among their subject, something that could explain the conflicting results, EIAH cannot be over looked since reportedly 50% of well trained athletes experience EIAH. One possible ergogenic effect of NaHCO3 would be to attenuate EIAH through an increase in blood pH in a subject. This has been shown previously by means of intravenous infusion during maximal rowing.

Aim: The aim of the study was to examine the effect of oral intake of NaHCO3 on EIAH and performance in trained cyclists.

Method: Seven male cyclists (age 23.7 (22-27) years, VO2peak 64 (60-72) ml min-1 (kg body mass) -1 volunteered for the study. The subjects performed two maximal exercise tests to exhaustion 48 hours apart in a counter balanced cross over double blind fashion. Subjects received 0.3 g kg BW-1 CaCO3 and 0.3 g kg BW-1 NaHCO3 in the placebo and bicarbonate trial respectively.

Free flowing arterialized capillary blood was sampled at rest and exhaustion and analyzed for pH, O2 Saturation, pO2, pCO2, and blood lactate. Ventilatory variables were measured continuously throughout the test V'O2, V’CO2, V'E, V'E/VO2, RER and HR. In addition pulse oximetry was used to evaluate O2 saturation.

Results/Discussion: At rest pH and PCO2 was elevated (p<0.05) in the bicarbonate trial compared to the placebo trial. At exhaustion in the bicarbonate trial pH, blood lactate, RER, was significantly elevated (p<0.05) when compared to the placebo trial. O2 saturation from blood samples at exhaustion in the bicarbonate trial showed a trend towards improving (p=0.061). No difference was seen between the two trials in PO2, VO2peak, V'Emax, HRmax or performance. During exercise, bicarbonate ingestion increased blood pH but did not improve arterial saturation or performance. The increase in blood pH achieved by ingestion of bicarbonate was not as large as the increase achieved by intravenous infusion in another study. Even with the larger increase in blood pH in those studies, there was only a small improvement in performance. One possible explanation for the performance improvement with bicarbonate infusion in that study was a reduced ventilation that could effect respiratory muscle work and thereby work capacity. The bicarbonate ingestion in the present study did not reduce ventilation. This could possible be achieved with higher doses of NaHCO3, which would most likely result in increased frequency of gastrointestinal distress among subjects.

Orientadores: Fernanda Paula Collares Queiroz, Sandra Cristina dos Santos Rocha
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O presente trabalho teve como objetivo o desenvolvimento de (i) micropartículas lipídicas contendo bicarbonato de sódio pelo processo de spray cooling e de (ii) aglomerados de bicarbonato de sódio, utilizando-se do processo de melt agglomeration em leito vibrofluidizado. Essas tecnologias foram aplicadas com o intuito de melhorar a estabilidade desse material, uma vez que o mesmo se decompõe na presença de umidade/ou temperaturas mais elevadas. Uma mistura lipídica composta por gordura de palma totalmente hidrogenada (GPTH) e óleo de palma refinado (OP) foi empregada como material de parede/ligante que atendeu ao requisito de ponto de fusão de 55 ºC, com a proporção de 57,5 e 42,5 %, respectivamente. No processo de spray cooling, foi realizado um Delineamento Composto Central Rotacional (DCCR), com 11 ensaios, para cada um dos três diâmetros de abertura de bico atomizador estudados (??igual a 1,0; 1,2 e 1,5 mm), totalizando 33 experimentos, a fim de se avaliar o efeito da temperatura de entrada da dispersão (Te) (65 a 85 ºC) e da pressão de atomização (Pat) (1,0 a 2,0 kgf/cm2) sobre as seguintes variáveis dependentes: (i) eficiência de microencapsulação (EM, % de CO2), (ii), quantidade de bicarbonato de sódio superficial (BSS, % de CO2) e (iii) rendimento (R, em %). As micropartículas apresentaram formato esférico e estrutura de superfície irregular para os ensaios realizados. A análise estatística dos resultados mostrou que para ??= 1,0 mm, um aumento nos níveis da Te e da Pat ocasionou um decréscimo da EM; para o ??= 1,2 mm, o aumento da Te ocasionou uma melhoria nessa resposta, entretanto, a Pat quando aumentada acarretou na sua diminuição. Para o ??= 1,5 mm, essas duas variáveis apresentaram menores efeitos, onde o aumento da Pat favoreceu a EM e o aumento da Te, a sua diminuição. A Te exerceu efeito positivo no R para o ??= 1,0 mm, sem influência nessa resposta para os diâmetros 1,2 e 1,5 mm, enquanto que a Pat teve efeito positivo para ??igual a 1,0 e 1,5 mm (termo linear) e negativo para o termo quadrático deste último. Pela combinação das respostas obtidas, verificou-se que o ensaio 4, diâmetro de bico atomizador (??= 1,5 mm), altas temperatura de entrada e de pressão de atomização (Te = 82 ºC e Pat = 1,85 kgf/cm2) apresentou o melhor desempenho (eficiência 3,18 %; quantidade de bicarbonato de sódio superficial 0,17 % e rendimento 80,0 %) quando comparado com os outros diâmetros de abertura. No processamento em leito vibrofluidizado, foi realizado um DCCR, totalizando 17 ensaios, com o objetivo de avaliar o efeito das variáveis: (i) pressão de atomização (5,0 a 15,0 Psig), (ii) frequência de vibração (186 a 354 rpm) e (iii) amplitude de vibração (0,40 a 2,00 cm), sobre as variáveis dependentes (i): rendimento R (%), (ii) eficiência da aglomeração Eagl (% CO2), para as frações granulométricas de 300, 600 e 840 µm, (iii) crescimento de partícula C3,3 (%) e (iv) índice de torrões Itor (%). O material aglomerado apresentou ampla distribuição de tamanho e a nucleação dos aglomerados ocorreu pelo mecanismo de imersão. Os aglomerados apresentaram Eagl diferentes para as frações avaliadas, sendo que a maior eficiência foi observada para a fração 840 µm, seguida das frações 600 e 300 µm. Contudo, através da comparação entre a Eagl e o C3,3, observou-se que a proteção não depende somente do tamanho da partícula, mas mais importante que isso é o mecanismo de formação do aglomerado, demonstrando a complexidade do processo. Com relação à proteção do material (avaliada pela Eagl), o efeito da pressão, da frequência e da amplitude foi positivo para as frações de 300 µm e 600 e 840 µm (termos quadráticos). Pela combinação das respostas, o ensaio que apresentou melhor desempenho no leito vibrofluidizado foi a de fração 840 µm, cujos parâmetros estavam fixados em baixos valores de pressão e frequência e alta amplitude. Os resultados demonstraram que ocorreu a proteção do bicarbonato de sódio contra a liberação de CO2 para ambos os processos estudados. As técnicas demonstraram grande potencial na produção desses materiais (bicarbonato de sódio microencapsulado e bicarbonato de sódio aglomerado), que se mostram viáveis para serem utilizados na formulação de um novo fermento químico, constituído pelo bicarbonato de sódio microencapsulado ou aglomerado e pelo componente ácido, sem a necessidade do agente inerte (amido) como separador físico
Abstract: This work had the objective of developing: (i) lipid microparticles containing sodium bicarbonate obtained by spray cooling process, and (ii) sodium bicarbonate agglomeration, obtained by melt agglomeration process in a vibrofluidized bed. These technologies were applied with the objective of improving the material stability, since it decomposes in the presence of humidity and/or higher temperatures. A lipid mixture composed of 57.5 % fully hydrogenated palm fat and 42.5 % refined palm oil, whose melting point is 55 ºC, was used. In the spray cooling process, a Central Composite Rotatable Design (CCRD) was applied, with 11 trials for each of the three nozzle atomizer diameters (?) studied (??= 1.0, 1.2 and 1.5 mm). Thirty three experiments were conducted with the objective of evaluating inlet temperature on the dispersion (65 to 85 ºC) and pressure atomization (1.0 to 2.0 kgf/cm2) on the following dependent variables: (i) microencapsulation efficiency (% CO2), (ii) amount of sodium bicarbonate on the surface (% CO2) and (iii) yield (%). The microparticles presented spherical shape and irregular surface. Statistical analysis showed that for ??= 1.0 mm and increases in levels of temperature on the dispersion and pressure atomization, the microencapsulation efficiency dropped. For ??= 1.2 mm, an increase in temperature on the dispersion led to an improvement in this response, however, when pressure atomization was increased, the microencapsulation efficiency fell. For ??= 1.5 mm, these two variables presented smaller effects, on the other hand, an increase in pressure atomization favored the microencapsulation efficiency. Increasing temperature on the dispersion, reduced the microencapsulation efficiency. Temperature on the dispersion presented a positive effect on yield for ??= 1.0 mm (this had no effect on the response for 1.2 and 1.5 mm diameters), while pressure atomization had a positive effect for d = 1.0 and 1.5 mm (linear term), its quadratic term had a negative effect on yield. By combining of dependent variables, it was found for ??= 1.5 mm, test 4, higher temperature on the dispersion and pressure atomization, presented the best performance (3.18 % higher efficiency, 0.17 % lower amount of surface sodium bicarbonate pressure and 80.0 % yield) when compared with the other diameters. In the vibrofluidized bed process, a CCRD was conducted, totaling 17 trials, to assess the effect of these independent variables: (i) atomization pressure (5.0 to 15.0 Psig), (ii) vibration frequency (186 to 354 rpm) and (iii) vibration amplitude (0.40 to 2.00 cm) on the dependent variables: (i) yield (%), (ii) agglomeration efficiency (% CO2), for the particle size fractions of 300, 600 and 840 µm (iii) particle growth (%) and (iv) lump. The agglomerated material presented ample size distribution and the nucleation mechanism occurred by immersion. The agglomeration efficiency presented different values for each fractions tested (300 µm <600 µm <840 µm). However, a comparison of agglomeration efficiency and particle growth, demonstrated that protection depends not only on particle size, but more on the formation mechanism of agglomeration particles, demonstrating its complexity. With regard to the protection of the material (assessed by agglomeration efficiency), the effect of pressure was positive for 300, 600 µm, and 840 µm fractions (quadratic terms), while the frequency had a positive effect for the three fractions. With respect to amplitude, the effect was positive on the larger particle size fractions. Considering all answers, the test that produced the best performance in the vibrofluidized bed was 840 µm fraction, whose parameters were set at low pressure and frequency values and high amplitude. The results showed that there was protection of sodium bicarbonate against the release of CO2 for both processes studied. The techniques demonstrated great potential in the production of these materials (microencapsulated sodium bicarbonate and agglomerated sodium bicarbonate particles), thus demonstrating its viability for use in the formulation of a new baking powder. A new baking soda, consisting of microencapsuled sodium bicarbonate or agglomerated and another acid compound, without the need for an inert agent (starch) as physical separator
Doutorado
Tecnologia de Alimentos
Doutor em Tecnologia de Alimentos

O presente trabalho teve como objetivo avaliar os efeitos de três diferentes aditivos (Levedura, Virginiamicina e Bicarbonato de sódio) na dieta de bovinos composta de 30% de silagem de milho e 70% de concentrado sobre alguns parâmetros do metabolismo ruminal (concentração de amônia, pH, protozoários ciliados), degradabilidade in situ da dieta e alguns parâmetros sanguíneos (pH, PCO2, PO2, TCO2, HCO3, Beefc, sO2 e lactato). Para tanto, quatro bovinos zebuínos, machos castrados, da raça Nelore, com cânulas ruminais e peso vivo médio de 295 Kg, foram utilizados em um experimento em quadrado latino 4 x 4 com 10 dias de adaptação e sete dias de colheita de amostras em cada período. Os animais foram alojados em galpão de alvenaria, com cochos e bebedouros individuais. No geral, houve uma diferença significativa no pH em todos os tratamentos nas primeiras 2 horas após a alimentação (P < 0,05), entretanto, não houve diferença entre os tratamentos nesse período. Já em relação aos parâmetros sanguíneos, o tratamento virginiamicina apresentou menor valor de pH em relação ao tratamento levedura (P < 0,10). No entanto, os tratamentos controle e bicarbonato de sódio não apresentaram diferença estatística (P < 0,10). Houve um aumento na concentração de oxigênio saturado (sO2) no tratamento levedura, enquanto no tratamento virginiamicina, o valor encontra se diminuído. Não houve diferença estatística entre os demais tratamentos (P > 0,05). Os demais parâmetros não apresentaram diferenças estatísticas (P > 0,05). Houve diferença significativa entre os tratamentos em todos os tempos. O tratamento com bicarbonato de sódio obteve maior concentração de protozoários, deferindo dos demais (P < 0,05). Os tratamentos levedura e virginiamicina, não diferiram entre si (P > 0,05). O tratamento controle apresentou a menor concentração de protozoários em relação aos demais tratamentos (P < 0,05). Não houve efeito significativo nos valores encontrados (P > 0,05) para amônia ruminal. Na degradabilidade, apenas o coeficiente de degradabilidade da matéria seca (CDMS) diferiu estatisticamente dos outros tratamentos (P < 0,05).
The present work had as objective evaluates the effects of three different addictive (Yeast, Virginiamycin and Bicarbonate of sodium) in the diet of bovine composed of 30% of corn silage and 70% of concentrated on some parameters of the metabolism ruminal (concentration of ammonia, pH, protozoa ciliated), degradability in situ of the diet and some sanguine parameters (pH, PCO2, PO2, TCO2, HCO3, Beefc, sO2 and lactato). For so much, four bovine zebu, castrated males, of the race Nelore, with stems ruminate and medium alive weight of 295 Kg, they were used in an experiment in Latin square 4 x 4 with 10 days of adaptation and seven days of crop of samples in each period. The animals were housed at masonry hangar. In the general, there was a significant difference in the pH in all of the treatments in the first 2 hours after the feeding (P < 0.05), however, there was not difference among the treatments in that period. Already in relation to the sanguine parameters, the treatment virginiamycin presented smaller pH value in relation to the treatment yeast (P < 0.10). However, the treatments control and bicarbonate of sodium didn\'t present statistical difference (P < 0.10). There was an increase in the concentration of oxygen saturated (sO2) in the treatment yeast, while in the treatment virginiamycin, the value finds if decreased. There was not statistical difference among the other treatments (P > 0.05). The other parameters didn\'t present statistical differences (P > 0.05). There was significant difference among the treatments in all of the times. The treatment with bicarbonate of sodium obtained larger concentration of protozoa, granting of the others (P < 0.05). The treatments yeast and virginiamycin didn\'t differ amongst themselves (P > 0.05). The treatment control presented to smallest concentration of protozoa in relation to the other treatments (P < 0.05). There was not significant effect in the found values (P > 0.05) for ammonia ruminal. In the degradability, just the coefficient of degradability of the matter dries (CDMS) differed of the other treatments (P < 0.05).

Photocatalytic inactivation of microorganisms by titanium dioxide (TiO2) is being studied as a water treatment technology. When TiO2 absorbs light, electrons (e~) and positive holes (h*) are formed inside the crystals that can migrate to the surface of TiO2- As a result, reactive oxygen species (ROS) such as O2'" and OH' are generated to damage microorganisms. The objective of this work was to investigate the effect of bicarbonate ion, both added and formed upon the photocatalytic oxidation of substrates, on TiO2 photocatalytic activity on the inactivation of viruses and enzymes, and the oxidation of proteins and amino acids. We examined the TiO2 photocatalytic inactivation of MS2, a single stranded RNA bacterial phage used as a model for human enteric viruses, and adenovirus, a double stranded DNA human enteric virus. Three proteins, P-galactosidase an enzyme that catalyzes the breakdown of lactose into galactose and glucose, Bovine Serum Albumin, a well-known transporter protein derived from the blood plasma of cows, and a tetrapeptide were examined. The kinetics of photocatalytic T1O2 oxidation of alanine, aspartic acid, cysteine, phenylalanine, serine, and tyrosine were also studied. These experiments were conducted in sterile water with and without added bicarbonate and in some cases in the presence of Ca** to remove bicarbonate formed in solution by photocatalytic oxidation of the substrate. We have found that bicarbonate considerably enhanced TiO>2 photocatalytic activity on the organism, protein, and amino acid levels due to CO3"" which was generated as a secondary radical by OH' reacting with the carbonate/bicarbonate ions present in our system. The CO3'\ a selective oxidant with longer life time, was more effective during photocatalytic treatment when compared to the highly reactive but non selective OH*. Therefore this knowledge can be used to enhance the photodegradation ofwastewater.

To evaluate interaction of water alkalinity and stocking density on body ionic levels, survival, growth and behavior of silver catfish, Rhamdia quelen, juveniles, a short-term experiment (96 h) analyzed the effect of three alkalinity levels (30, 80 and 130 mg/L CaCO3) and four stocking densities (4, 8, 16, and 24 g/L). In addition, a growth experiment of 30 days verified the effect of three stocking densities (4, 8, 16 g/L) and the same alkalinity levels. Survival and body ionic levels were not significantly affected in the short-term experiment, but after 30 days survival was significantly reduced in the group maintained at the stocking density of 16 g/L and 30 mg/L CaCO3. However, this treatment provided higher weight and specific growth rate compared to the treatment with the highest alkalinity and the same stocking density. The time of capture of the food, in both experiments, was faster in the treatments of high stocking density. In the short-term experiment fish remained mainly in the bottom, and the reduction of stocking density increased swimming speed. The color of the animals was significantly clearer in the lowest densities of the growth experiment. Agonistic side behaviors prevailed in the lowest alkalinities of the stocking density of 8 g/L, and cannibalism occurred only in the stocking density of 8 g/L and alkalinity of 130 mg/L CaCO3 of the growth experiment. The stocking density of 16 g/L and alkalinity of 80 mg/L CaCO3 seems to be the most appropriate for silver catfish juveniles growth in these experimental conditions.
Com o objetivo de avaliar a interação da alcalinidade da água com diferentes densidades de estocagem sobre os níveis iônicos corporais, sobrevivência, crescimento e comportamento de juvenis de jundiá, Rhamdia quelen, delineou-se um experimento de curta duração (96 h) com três níveis de alcalinidade (30, 80 e 130 mg/L CaCO3) e quatro densidades de estocagem (4, 8, 16 e 24 g/L). Além disso, em um experimento de crescimento (30 dias) testou-se três densidades de estocagem (4, 8, 16 g/L) e as mesmas alcalinidades. A sobrevivência e os níveis iônicos corporais não foram afetados no experimento de curta duração, mas após 30 dias a sobrevivência foi reduzida no tratamento de maior densidade e menor alcalinidade. Este mesmo tratamento foi o que obteve melhores resultados de peso e taxa de crescimento específico em relação à maior alcalinidade da mesma densidade. O tempo de captura do alimento, em ambos experimentos, foi mais curto nos tratamentos de maior densidade. No experimento de curta duração os peixes se concentravam mais no fundo à medida que se diminuía a densidade de estocagem e com o aumento desta aumentou a velocidade de natação. A coloração dos animais foi significativamente mais clara nas menores densidades do experimento de crescimento. Confrontos laterais predominaram nas menores alcalinidades da densidade de 8 g/L, canibalismos ocorreram apenas na densidade de 8 g/L e alcalinidade de 130 mg/L CaCO3 do experimento de crescimento. A utilização da densidade de estocagem de 16 g/L e alcalinidade de 80 mg/L CaCO3 é a mais adequada para o cultivo de juvenis de jundiá nestas condições experimentais.

Introdução: Nefropatia induzida por contraste (NIC) está associada a piores desfechos intra-hospitalar e a longo prazo. Estudos recentes sugerem que hidratação com bicarbonato de sódio possa ser útil na sua prevenção; no entanto, essa medida de prevenção de NIC não foi, ainda, avaliada em pacientes diabéticos. Método: Subanálise de um estudo multicêntrico envolvendo 301 pacientes com creatinina sérica ≥ 1,2 mg/dl ou depuração de creatinina endógena (DCE) < 50 ml/min submetidos a cineangiocoronariografia ou angioplastia coronária, randomizados para receber hidratação com bicarbonato de sódio ou solução salina (soro fisiológico – SF) a 0,9%. Todos os procedimentos foram realizados com contraste iônico de baixa osmolaridade. Os desfechos avaliados foram incidência de NIC (definida como aumento de 0,5 mg/dl) e variação da creatinina e da DCE em 48 horas após o procedimento. Da totalidade de pacientes, 87 tinham diabetes melito e foram incluídos nesse subestudo. Resultados: Não houve diferença entre os grupos em relação a características demográficas, volume de contraste e níveis basais de creatinina e DCE. Entre os pacientes avaliados, 8 desenvolveram NIC: 4 (9,8%) pacientes no grupo bicarbonato e 4 (8,9%) no grupo SF 0,9% (p = 0,9). A variação da creatinina sérica e da DCE foi similar entre os grupos. Conclusão: Hidratação com bicarbonato de sódio não demonstrou benefício em reduzir a incidência de NIC em pacientes diabéticos submetidos a cateterismo cardíaco ou angioplastia coronária em comparação à hidratação com SF 0,9%.
Background: Contrast-induced nephropathy (CIN) is associated with worse clinical outcomes both at short and long-term follow-up. Recent evidence indicates that intravenous hydration with sodium-bicarbonate may reduce the incidence of CIN. However, this strategy has not been reported in diabetic patients. Methods: Sub-analysis of a multicenter study involving 301 patients with serum creatinine ≥ 1,2 mg/dL or creatinine clearance < 50 mL/min submitted to coronary angiography or percutaneous coronary intervention and randomized to intravenous hydration with sodium-bicarbonate or normal saline. All patients received low-osmolar contrast media. We assessed the incidence of CIN (defined as creatinine increase ≥ 0,5 mg/dL), and the average change in creatinine and creatinine clearance 48 hours after the procedure. A total of 87 diabetic patients were analyzed. Results: There was no difference between groups regarding baseline characteristics, contrast volume used, baseline creatinine levels and creatinine clearance. Eight patients presented CIN: 4 (9.8%) in the bicarbonate group and 4 (8.9%) in the saline group (p = 0.9). The average change in serum creatinine and creatinine clearance were similar between groups. Conclusion: Intravenous hydration with sodium-bicarbonate did not reduce the incidence of CIN in diabetic patients undergoing coronary angiography or percutaneous coronary intervention as compared to hydration with normal saline.

The use of sodium bicarbonate (NaHCO3) as an ergogenic aid has been widely researched and also practiced by the athletic community. Despite this, fundamental issues have not been addressed, including a full profile of NaHCO3’s effects on the bicarbonate ion (HCO3-), the dose-dependent effects on performance and gastrointestinal discomfort (GI), and the most optimal timing of ingestion. Recently, an individualised NaHCO3 ingestion strategy has been advocated, which entails supplementing NaHCO3 at a pre-determined time to peak pH or HCO3-. The reproducibility of both the blood and performance responses using this strategy remains unknown however, and therefore Study 1 investigated the reproducibility of the blood acid base balance responses following NaHCO3 ingestion in two separate doses of 0.2 g.kg-1 BM (SBC2) and 0.3 g.kg-1 BM NaHCO3 (SBC3). This study revealed that pH and HCO3- kinetics following both doses were highly reproducible, although HCO3- displayed greater reproducibility. Furthermore, both doses increased pH and HCO3- to a level that would suggest ergogenic benefits could be elicited. As a result, both the reproducibility of the performance responses (Study 2) and the performance effects against a placebo (Study 3) were investigated following both SBC2 and SBC3, administered at a pre-determined individual time to peak HCO3-. Both SBC treatments revealed highly reproducible performance responses, and displayed similar improvements in performance compared to a placebo during a 4 km cycling time trial (TT). Once methods to enhance the application of NaHCO3 to exercise performance in normoxia were identified, this supplement was then applied to acute hypoxia and recovery. Study 4 investigated the effects of NaHCO3 ingestion on 4 km TT performance at acute moderate hypoxia (~3000 m). Again, both SBC treatments improved performance compared to placebo. The acid base balance recovery profile following exercise was also monitored for 40 min post-exercise, whereby both SBC treatments displayed a similar magnitude of acid base balance recovery compared to a placebo. Study 5 therefore investigated the effects of both SBC2 and SBC3 on repeated 4 km TT (TT1 and TT2) cycling, interspersed by a 40 min recovery at acute moderate hypoxic conditions (~3000 m). Repeated efforts were improved more greatly following SBC3, revealing significant improvements vs. placebo in both TT1 and TT2, and a greater magnitude of effect compared to SBC2. Collectively, these studies highlight the importance of the dose, and timing of NaHCO3 ingestion to improve exercise performance both at normoxia and hypoxia.

El objetivo de la presente tesis fue estudiar el efecto de algunos factores relacionados con el comportamiento, y el uso de bicarbonato sódico, sobre los procesos digestivos que afectan la función ruminal en terneros de cebo intensivo alimentados con pienso y paja ad libitum. En el primer experimento, 4 terneras Frisonas fistuladas en el rumen fueron asignadas a un Cuadrado Latino 4 × 4 para determinar el efecto del aumento en la concentración de bicarbonato sódico (0, 1,25, 2,50 y 5 % de la MS del pienso) sobre la ingestión, el consumo de agua, la fermentación ruminal, y los comportamientos de masticación e ingestión. La ingestión de pienso disminuyó mientras que la de paja aumentó linealmente con el aumento de bicarbonato. El consumo de agua aumentó linealmente sólo cuando se expresó en L/kg de MS. La media y el valor mínimo del pH diario del líquido ruminal no fueron afectados. Sin embargo, el pH ruminal aumentó linealmente a las 2 y 4 h post-alimentación, y el número de horas con pH ruminal por debajo de 5,8 mostró altos valores en el tratamiento sin bicarbonato. La proporción molar de propionato en rumen disminuyó linealmente, mientras que las proporciones de acetato, butirato y ácidos grasos volátiles no-ramificados aumentaron linealmente con el nivel de bicarbonato. La frecuencia de las comidas y la velocidad de ingestión disminuyeron linealmente. El tiempo comiendo por unidad de ingestión (min/kg MS) aumentó linealmente con el nivel de tampón. En el segundo experimento, se utilizaron 72 terneras Frisonas distribuidas en un diseño factorial con 3 tratamientos y 3 bloques con similar peso vivo para estudiar el efecto de la competencia social sobre la producción, el comportamiento y el bienestar durante las 4 semanas siguientes a la llegada al cebadero. Los tratamientos consistieron en aumentos en el nivel de competencia social a través del uso de 1, 2 y 4 espacios en el comedero de pienso por corral (8 terneras/corral). Hubo una disminución lineal en la ingestión de pienso y en el crecimiento durante la semana 1 después de la llegada al cebadero pero el efecto fue cuadrático durante las semana 3 y 4, con valores bajos cuando la competencia fue más alta. El consumo de paja y la variabilidad del crecimiento entre terneras dentro de cada corral tendieron a aumentar linealmente con el aumento en la competencia. El aumento de competencia por el pienso aumentó los efectos de la dominancia sobre el crecimiento, siendo su relación negativa en la primera pero positiva en la tercera semana. Los mismos animales con el mismo diseño experimental se utilizaron para estudiar el efecto de la competencia sobre la fermentación ruminal, la producción y el bienestar durante 6 períodos experimentales de 28 días cada uno. La ingestión de pienso disminuyó linealmente pero esto no afectó a ningún parámetro productivo. Hubo un alto porcentaje de hígados con abscesos en el nivel más alto de competencia. El tiempo diario comiendo pienso disminuyó, mientras que su velocidad de ingestión, el tiempo diario de pie y el número de agresiones aumentaron con la competencia. La corticosterona en heces mostró altos valores sólo en animales dominantes del nivel más alto de competencia. La concentración de haptoglobina en sangre aumentó linealmente, particularmente en las terneras mas subordinadas. El aumento en la competencia redujo el pH ruminal sólo en los primeros 2 períodos, y la proporción de terneras que mostraron un pH ruminal menor a 5,6 y la concentración de ácido láctico aumentaron linealmente. Esta tesis muestra que el comportamiento de la alimentación de los terneros en cebo intensivo permite entender mejor el funcionamiento ruminal y procurar así su bienestar.
The objective of the present thesis was to study the effects of some behavioral factors, and the use of sodium bicarbonate, on the digestion processes affecting ruminal function of beef cattle fed concentrate and straw ad libitum. In the first experiment, four ruminally fistulated Holstein heifers were used in a 4 x 4 Latin square design to determine the effect of increasing levels of sodium bicarbonate (0, 1.25, 2.50 and 5 %, on concentrate DM basis) on intake, water consumption, ruminal fermentation, and chewing and feed intake behaviors. Concentrate and barley straw were fed once daily at 0830 and ad libitum. Concentrate decreased and straw DMI increased linearly with buffer level. Water consumption increased linearly when expressed in L/kg of DMI but not in L/d. Daily mean and lowest ruminal pH were not affected by treatments. However, ruminal fluid pH increased linearly at 2 and 4 h after feeding and the number of hours in which ruminal pH was below 5.8 was greatest when no buffer was added. Daily average molar proportion of propionate decreased linearly but acetate, butyrate, and branched-chain VFA increased linearly as the level of bicarbonate increased. Meal frequency and eating rate decreased linearly. Time spent eating per unit of DMI increased linearly with buffer level. In the second experiment, 72 Friesian calves were distributed in a factorial design with 3 treatments and 3 blocks of similar fasted BW to study the effect of increasing competition on performance, behavior, and welfare indicators throughout the 4 wk after arrival. Treatments consisted of increasing levels of social competition with the use of 1, 2 or 4 concentrate feeding places/pen (8 calves/pen). Concentrate and straw were fed ad libitum at 0830 and in individual feeders. Increasing competition resulted in a linear decrease of concentrate DMI and ADG during wk 1 after arrival but the response was quadratic in wk 3 and 4, being lowest at the greatest competition. Straw intake and the within-pen SD of ADG tended to increase linearly with competition during the 4-wk receiving period. Increasing competition at the concentrate feeders reduced lying time, increased standing time, and changed the diurnal feeding pattern (concentrate eating time decreased but straw eating time increased during peak feeding times). Increasing social competition at the concentrate feeders accentuated the effects of dominance rank on ADG, with their relationship being negative at wk 1 but positive at wk 3. The same 72 heifers with the same experimental setup were used to study the effect of increasing competition on performance, behavior, welfare, and ruminal fermentation of feedlot heifers. After the 4-wk adaptation period, DMI and ADG were measured, and blood and rumen samples were taken during 6, 28-d experimental periods. Fecal corticosterone and behavior were measured at periods 1, 3 and 6. Concentrate intake decreased linearly with competition but final BW, ADG, and G:F ratio were not affected by treatments. The proportion of abscessed livers responded quadratically with high proportion at the greatest competition. Concentrate eating time decreased, and eating rate, standing time, and aggressions increased linearly with competition for concentrate. The pen-average fecal corticosterone was not affected by treatments but that of dominants responded quadratically, being greatest with the greatest competition. Serum haptoglobin concentration increased linearly with competition, particularly within the most subordinate heifers. Increased competition reduced ruminal pH only in periods 1 and 2 but tended to increase the proportion of heifers with ruminal pH below 5.6 and increased ruminal lactate. The present thesis shows that feeding behavior in beef cattle allows better understand ruminal function and to assess welfare as well.

Objectius: Comparar l’efectivitat de la infusió de llantèn o clorhexidina al 0,12% versus la dissolució aqüosa de bicarbonat sòdic al 5%, en el tractament simptomàtic de la mucositis oral. Hipòtesi: El temps de curació de la mucositis oral mitjançant infusió de llantèn o clorhexidina al 0,12% serà inferior que amb bicarbonat sodic 5%. Metodologia: Estudi multicèntric, assaig clinic fase III aleatoritzat, triple cec. Mostra estimada de 45 pacients (15 per branca) afectes de tumor sòlid amb mucositis grau II-III durant la quimioteràpia (α:5%, β: 20). Període Inclusió: 2006 a 2009. Els pacients foren randomitzats a rebre durant un brot de mucositis: *Branca A: Bicarbonat sòdic 5% + Bicarbonat sòdic 5%; *Branca B: Bicarbonat sòdic 5% + infusió de llantèn; *Branca C: Bicarbonat sòdic al 5% + Clorhexidina al 0,12%; durant un període de tractament de 14 dies. Les variables d’estudi foren: grau de mucositis (OMS), dolor (EVA), qualitat de vida (EORTC QLQ-C30), nivells de neutròfils, fàrmac i dosi de quimioteràpia rebuda, pes, ingesta i dades sociodemogràfiques. Els pacients varen ser avaluats presencialment el dia 0, 7, 14 o curació; així com monitoritzats diàriament amb diari de camp i trucada telefònica. S’han obtingut els permisos necessaris de l’AEMPS i CEICs de referència. Resultats: Foren randomitzats 60 pacients dels quals han estat avaluats 50 participants per retirada de 10 pacients. El 38% (19) de la mostra se van rebre glopeig amb Bicarbonat-Clorhexidina, un 32% (16) va rebre Bicarbonat-Bicarbonat i la resta glopeig de Bicarbonat-Llanten. El 52% (26) dels casos foren dones, amb una edat situada en 59,5 anys (DS: 14,3). La mitjana de cicles de tractaments quimioteràpics realitzats fou de 3,6 (DS: 3,2). El 65,3% (32) dels pacients van rebre algun tipus de tractament mucotòxic en el darrer cicle de quimioteràpia. Els participants presentaren a l’inici de l’estudi un nivell de mucositis de grau II en el 86% (43) dels casos, essent la resta de grau III. El dolor mig basal fou de 4 punts (DS: 2,6) segons EVA. El temps mig de tractament per al global de la mostra fou de 8,8 dies (DS: 4,1), rang 2 a 14 dies. Dels 50 pacients inclosos, 34 d’ells arribaren a la curació total (grau 0), presentant una diferència de 2 dies d’evolució a favor del glopeig exclusiu de bicarbonat, 5 dies [IC 95%: 3,99-6,55] front als grups amb clorhexidina 7 dies [IC 95%: 5,33-8,98] i llanten 7 dies [IC 95%: 5,27-8,53] (p=0,991). El grau de dolor dels pacients va evolucionar favorablement durant els 14 dies de tractament situant-se al final de l’estudi amb un EVA=1 (DS:1,8), no s’apreciaren diferencies segons el glopeig (p=0,762). Al finalitzar els 14 dies de tractament, un 98% (49) dels pacients toleraven liquids i solids sense diferencies pel glopeig rebut (p=0,702). La qualitat de vida global basal fou de 53 punts (DS: 21,2) de mitjana (rang 0 a 83), sense millora a la resolució de la mucositis. No s’observa diferència en l’evolució de la qualitat de vida dels pacients entre el pre i el post tractament de la mucositis (p=0,670), ni segons glopeig (p=0,164) No existeixen diferències concloents vers el millor glopeig en el tractament de la mucositis oral, però cal destacar la rellevància clínica de l’ús dels glopejos de bicarbonat sòdic exclusivament, els quals milloren el temps de curació respecte a la resta. El procés evolutiu de la mucositis oral provoca una millora en el control del dolor amb el pas del temps. No s’aprecien diferències en la qualitat de vida dels pacients a l’inici i final de la mucositis. Les àrees emocionals i socials presenten major afectació, així com una major presència d’anorexia i fatiga.
Objectives: To compare the effectiveness of Plantago major solution on the one hand and on the other Chlorhexidine 0.12% in the symptomatic treatment of oral mucositis compared to Bicarbonate 5% Aqueous solution (S.B.5%) on solid tumor cancer patients treated at the Catalan Institute of Oncology and the Hospital Spirit Sant Foundation between 2006 and 2009. Methodology: Multicenter, experimental, randomized phase III clinical trial, triple-blind study with three types of rinses to evaluate treatment of oral mucositis secondary to Chemotherapy. We estimated a sample of 45 patients (15 for arm) affected by solid tumor with mucositis grade II-III during (α: 5% β: 20). Patients were randomized to receive one of three treatment arms, with two types of oral rinses during a single outbreak of mucositis: (A) with S.B.5%+S.B.5% (B) with S.B.5%+Plantago Major solution, (C) with S.B.5%+Chlorhexidine 0.12%; during a treatment period of 14 days. Variables: demographics, neutrophil level, drug and dose of chemotherapy received, severity of mucositis (WHO scale), pain intensity (VAS) and Quality of life (EORTC QLQ-30). Results: Fifty patients were evaluated after excluding 10 of the 60 randomised patients that were eligible. Of the cases 52% (n=26) were women. All participants were Caucasian, with mean age 59.5 years (SD 14.3). Of the 50 patients enrolled, 34 (68%) achieved complete healing or degree 0, showing a difference of 2 days for the exclusive bicarbonate rinse - 5 days [CI 95%, 3.99-6.55] compared to Chlorhexidine groups - 7 days [CI 95%, 5.33-8.98] and Plantago Major – 7 days [CI 95%, 5.27-8.53]. Differences on the degree of pain did not show statistical significance with regard to any of the rises types (p=0.762). No difference was observed in the evolution of the quality of life of patients between the pre and post treatment of mucositis (p=0.670), or with the application or not of different types of experimental treatment (p=0.164) Conclusions: The bicarbonate solution improved the healing time and decreased the symptoms such as pain, compared to the rest of solutions; however no conclusive difference between the efficacy of the three solutions were found among this population.

The aim of this study was to evaluate the efficiency of cleaning methods in removing pigment deposited on aesthetic brackets, after immersion in coffee. We selected 160 premolar brackets (80 monocrystalline and polycrystalline 80). The brackets were fixed on a glass blade and soon, thereafter, color measurement was performed using a spectrophotometer (T0). For each means of immersion, 80 brackets were selected (40 for each type of ceramic). Soon after staining (30 days of immersion), new color measurements were made (T1). Subsequently, the specimens were divided randomly into four groups for brushing, bleaching, blasting with sodium bicarbonate jet and sodium bicarbonate jet followed by bleaching. New color measurements were made after each cleaning method was used (T2). The color change of the brackets was evaluated according to two formulae, i.e., CIELAB and CIEDE2000. The differences between the average ΔE according to treatment, bracket, and solution were evaluated by linear regression analysis. The greatest staining was caused by coffee. The crystalline structure did not influence the color change. The methods with lower averages of ΔE for coffee were sodium bicarbonate jet followed by bleaching and bleaching, followed by the group that received brushing and sodium bicarbonate jet (both CIELAB as to CIEDE2000). The CIEDE2000 formula was more sensitive in detecting non-acceptable and perceptible differences in color when compared with the CIELAB formula. It was concluded that the most effective methods to remove pigment deposited on aesthetic brackets are sodium bicarbonate jet followed by bleaching and bleaching alone.
O objetivo desse estudo foi avaliar a eficiência dos métodos de limpeza na remoção de pigmentos depositados sobre bráquetes estéticos, após imersão em café. Foram selecionados 160 bráquetes (80 monocristalinos e 80 policristalinos) de pré-molares superiores. Os bráquetes foram fixados em uma lâmina de vidro e logo depois a mensuração de cor foi realizada com um espectrofotômetro (T0). Cada meio de imersão (café ou saliva) continha 80 bráquetes (40 para cada tipo de cerâmica). Logo após a coloração (30 dias de imersão) novas aferições foram feitas (T1). Posteriormente, os espécimes foram divididos randomicamente em 4 grupos: Grupo 1 Escovação; Grupo 2 Clareamento; Grupo 3 Jateamento com bicarbonato de sódio; Grupo 4 Jateamento com bicarbonato de sódio seguido de Clareamento. Novas aferições foram feitas depois de cada método de limpeza (T2). A variação da cor dos bráquetes foi avaliada de acordo com 2 fórmulas: CIELAB E CIEDE2000. As diferenças entre as médias de ΔE de acordo com o tratamento, braquete e solução foram avaliadas através de análise de regressão linear. O café promoveu maior manchamento. A estrutura cristalina não influenciou na alteração de cor. Os métodos com menores médias de ΔE, no café, foram o jateamento com posterior clareamento e o clareamento sozinho, seguido dos grupos que receberam jateamento e escovação (tanto para CIELAB quanto para CIEDE2000). A fórmula CIEDE2000 foi mais sensível em detectar diferenças de cor não-aceitáveis e perceptíveis quando comparado à fórmula CIELAB. Conclui-se que os métodos mais eficazes na remoção de pigmentos depositados sobre bráquetes estéticos são o jateamento com bicarbonato de sódio com posterior clareamento e o clareamento sozinho.

Este estudo in vitro avaliou o efeito do bicarbonato de sódio 10% (BS) e do hidrogel de ascorbato de sódio 10% (AS) na resistência adesiva à microtração de uma resina composta unida à superfície de esmalte bovino clareado com peróxido de hidrogênio 35% (PH). Cento e vinte superfícies de esmalte vestibular com dimensões de 4mmX4mm de incisivos bovinos foram planificadas e separadas em cinco grupos: C - não clareado e restaurado; OI - clareado com PH e restaurado imediatamente; O7 - clareado com PH, armazenado por 7 dias em água destilada e restaurado; OBS - clareado com PH, BS 10% durante 5 min e restaurado; OAS - clareado com PH, AS 10% durante 15 min e restaurado. O gel de PH (Total Blanc Office, Nova DFL) foi aplicado duas vezes de 20 minutos em cada espécime e as restaurações foram confeccionadas com sistema adesivo restaurador (Natural Bond DE + Natural Look, Nova DFL). Após uma semana, os espécimes foram seccionados para obtenção de palitos com 1,00 mm2 de área média e submetidos ao teste de microtração em máquina de teste universal a 0,5mm/min, imediatamente e após 6 meses. As falhas foram avaliadas em estereomicroscópio digital (200x) e classificadas em: adesiva, coesiva em esmalte, coesiva em resina e mista. Os dados foram analisados por ANOVA a dois critérios e teste de Tukey para comparações múltiplas (p<0,05). Os valores médios de resistência adesiva (MPa ± DP; imediatamente / 6 meses) foram: C (24,22 ± 7,74 Ba / 20,13 ± 6,43 BCa); OI (18,29 ± 5,88 Ca / 25,85 ± 5,23 Ab); O7 (40,88 ± 7,95 Aa / 24,61 ± 7,83 ABb); OBS (19,95 ± 5,67 BCa / 15,94 ± 5,57 CDa); OAS (24,43 ± 6,43 Ba / 13,69 ± 5,58 Db). Das estratégias antioxidantes avaliadas após 7 dias, os grupos OAS e OBS não diferiram estatisticamente do grupo C, nem OBS diferiu estatisticamente do grupo OI. Nesse período de avaliação, somente o grupo O7 apresentou diferença significativa em relação aos demais grupos. Após 6 meses de envelhecimento, apenas O7 e OBS apresentaram desempenho semelhante estatisticamente ao grupo C. O percentual de falhas (7 dias / 6 meses) foi: adesiva (65,26% / 67,06%); coesiva em esmalte (14,74% / 24,71%); coesiva em resina (1,58% / 2,35%); mista (18,42% / 5,88%). Em função dos resultados apresentados, a estratégia mais segura é aguardar 7 dias após o clareamento para a realização de restaurações adesivas. Quando não for possível aguardar este tempo, a aplicação de bicarbonato de sódio 10% por 5 minutos sobre o esmalte clareado deve ser feita.
This \"in vitro\" study evaluated the effect of 10% sodium bicarbonate (SB) and 10% sodium ascorbate (SA) hydrogel on the composite resin microtensile bond strength of bleached bovine enamel with 35% hydrogen peroxide (HP). One hundred and twenty buccal enamel surfaces with dimensions of 4mmX4mm of bovine incisors were flattened and separated into five groups: C - not bleached and restored, OI - bleached with HP and immediately restored; O7 - bleached with HP, stored for 7 days in distilled water and restored; OBS - bleached with HP, 10% SB for 5 min and restored; OAS - bleached with HP, 10% SA for 15 min and restored. HP gel (Total Blanc Office, Nova DFL) was applied twice for 20 minutes on each specimen and the restorations were performed with an adhesive restorative system (Natural Bond DE + Natural Look, Nova DFL). After a week, the specimens were sectioned into sticks with a 1.00 mm2 average area and submitted to a microtensile test in a universal testing machine at 0.5 mm/min, immediately and after 6 months. The failures were evaluated in a digital stereoscope (200x) and classified as: adhesive, cohesive in enamel, cohesive in resin and mixed. Data was analyzed by two-way ANOVA and Tukey\'s test for multiple comparisons (p <0.05). The average values of the bond strength (MPa ± SD; immediately / 6 months) were: C (24.22 ± 7.74 Ba / 20.13 ± 6.43 BCa) OI (18.29 ± 5.88 Ca / 25.85 ± 5.23 Ab); O7 (40.88 ± 7.95 Aa / 24.61 ± 7.83 ABb), OBS (19.95 ± 5.67 BCa / 15.94 ± 5.57 CDa), OAS (24.43 ± 6.43 Ba / 13.69 ± 5.58 Db). Among the antioxidant strategies evaluated after 7 days, the OAS and OBS groups did not differ from group C and neither OBS group differed from the OI group. In the same evaluation period, only the O7 group presented a significant difference compared to the other groups. After 6 months of aging, only the O7 and OBS groups performed statistically similar to group C. The percentage of failures (7 days / 6 months) was: adhesive (65.26% / 67.06%); cohesive in enamel (14.74% / 24.71%); cohesive in resin (1.58% / 2.35%); mixed (18.42% / 5.88%). According to the results presented, the safety strategy is waiting 7 days after bleaching for the adhesive restorative procedures. When this waiting period is not possible, 10% sodium bicarbonate should be applied for 5 minutes on the bleached enamel.