Water is arguably the most important nutrient given that even minor deficits lead to performance detriment for athletes and, in a matter of days, total absence causes fatality for all. Despite this, several reports suggest that an overwhelming amount of the athletic population competes and trains in a dehydrated state. The impact of dehydration on leisure sports, such as golf, is less certain given that fine motor skill sports have received less attention in the literature and that existing research on dehydration and golfers is largely limited to males. In this randomized, controlled, crossover pilot experiment, elite female golfers on the Virginia Tech Women’s Golf Team (n=6) completed four laboratory simulated golf holes in both euhydrated and dehydrated states. Euhydration (mean urinary specific gravity [USG]=1.009; range=1.003–1.021) was attained by following the NCAA hydration guidelines, and dehydration (mean USG=1.021; range=1.018–1.026) was attained via a 12 hour overnight fast from fluids. No significant interactions of condition by time for perceived effort, 7-iron distance and accuracy, putting accuracy, reaction time, and executive cognitive function were found between euhydrated and dehydrated states. However, although not significant, euhydrated participants demonstrated improved 7-iron and putting accuracy and reported less perceived effort as compared to performance during their dehydrated state. Based on USG levels, NCAA hydration recommendations may not be adequate to induce a euhydrated state for all athletes. More research is needed with larger sample sizes to further elicit the impact of hydration status on variance in motor and cognitive function for elite golfers. / Masters of Science / Besides oxygen, our bodies need water more than anything else to function. Water is so vital to health that its absence can cause death in just three days. Athletic populations, in particular, should aim for adequate hydration to optimize sport performance, to avoid heat illness, and to promote overall health and wellbeing. Despite this importance, few studies have investigated the impact of hydration status on athletic performance of golfers, and of these studies, none have been done with females. In this experiment, female golfers on the Virginia Tech Women’s Golf Team (n=6) completed four laboratory simulated golf holes in both euhydrated and dehydrated states. Adequate hydration (euhydration) was attained by following the NCAA hydration guidelines, and dehydration was attained by restricting participants from drinking any fluid for 12 hours overnight. Performance in both adequate hydration and dehydration was measured by perceived effort, 7-iron distance and accuracy, putting accuracy, reaction time, and executive cognitive function. No significant interactions for any of the measures resulting in differences over time were found. However, although not significant, euhydrated participants demonstrated greater 7-iron and putting accuracy and reported less perceived effort as compared to performance during their dehydrated state. One participant did not reach adequate hydration by following the fluid intake guidelines during the hydration visit; therefore, NCAA hydration recommendations may not adequately hydrate all collegiate athletes. More research is needed with larger sample sizes to determine the impact of hydration status on motor and cognitive function of elite female golfers.

<p>U ovom radu je obrađen postupak spontane fermentacije tradicionalnog proizvoda, fermentisanog kupusa u glavicama. U prvom delu urađena je karakterizacija domaće tradicionalne populacije Futo&scaron;ki u odnosu na uvozni hibrid Bravo. Na osnovu PCA analize i analize standardnih ocena SS fizičkih, hemijskih i senzorskih paramentara odabrani su uzorci povoljni za proces fermentacije. Proces fermentacje je obavljen na temperaturama 16-18^oC, 18-20^oC i 20-20^oC, i sa razliĉitim koncentracijama soli od 1, 1,5 i 2 %. Analizirani su fizički, hemijski, mikrobiolo&scaron;ki parametri i senzorske osobine kupusa tokom fermentacije. Metodom odzivne povr&scaron;ine sa analizom varijanse (ANOVA) modela odziva za svaki od analiziranih karakteristika i obja&scaron;njeno je koji od parametara procesa temperatura, koncentracija soli i vreme trajanja procesa ima statistiĉki značajan uticaj na formiranje matematiĉkih modela odziva, prikazanih u obliku polinoma drugog reda (SOP). Zaključeno je da Futo&scaron;ki kupus postiţe brţe zavr&scaron;nu taĉku fermentacije u odnosu na hibrid Bravo. Drugi kori&scaron;ćeni tehnolo&scaron;ki postupak u ovom radu je osmotska dehidratacija. Kupus je dehidriran u tri osmotska rastvora (vodeni rastvor natrijum hlorida i saharoze, kombinacija vodenog rastvora natrijum hlorida i saharoze i melase i melasa &scaron;ećerne repe) različitih koncentracija, na tri temperature (20&deg;C, 35&deg;C i 50&deg;C) i pri tri vremena trajanja procesa (1, 3 i 5h). Mereni i računati odzivi procesa osmotske dehidratacije bili su: sadržaj suve materije, gubitak vode, prirast suve materije i indeks efiksanosti procesa. Rezultati ispitivanja pokazuju da povećanje tehnolo&scaron;kih parametara temperature i vremena procesa, kao i koncentracije osmotskih rastvora dovode do intenziviranja prenosa mase u procesu i povećanja vrednosti odzivnih parametara procesa. Takođe, zaključeno je da tokom osmotske dehidratacije u melasi &scaron;ećerne repe dolazi do obogaćivanja kupusa nutritivnim komponentama, naročito kalijumom. Treći segment ovog rada je analiza održivosti osmotski dehidriranog kupusa pakovanog u modiifikovanoj atmosferi dve različite sme&scaron;e gasova N₂ i CO₂. Analizom hemijskih, mikrobiolo&scaron;kih i senzorskih svojstava zaključeno je da ovaj osmotski dehidriran kupus pakovan na navedeni način ima održivost od 90 dana.</p> / <p>This paper describes the process of spontaneous fermentation of traditional product, fermented whole cabbage. In the first part characterization of the local traditional type Futo&scaron;ki cabbage in relation to imported hybrid Bravo was done. Based on the PCA analysis and analysis of the standard score SS physical, chemical and sensory parameters favorable samples for the process of fermentation were selected. The process of fermentation was carried out at three temperatures: 16-18^oC, 18-20^oC and 20-20^oC, and with various concentrations of salt: 1, 1.5 and 2%. The physical, chemical and microbiological parameters, as well as sensory properties of cabbage during fermentation were analyzed. Response surface method with analysis of variance (ANOVA) model response for each of the analyzed characteristics was used and it was explained which of the process parameters (temperature, salt concentration and the duration of the process) had a statistically significant effect on the formation of mathematical models of response, presented in the form of a second order polynomial (SOP). It was concluded that Futo&scaron;ki cabbage faster achieved end point of fermentation as compared to a hybrid Bravo. Another technological method used in this investigation was the osmotic dehydration. Cabbage was dehydrated with three osmotic solutions (an aqueous solution of sodium chloride and sucrose; the combination of an aqueous solution of sodium chloride and sucrose with molasses; sugar beet molasses) of different concentrations, at three temperatures (20&deg;C, 35&deg;C and 50&deg;C) and at three times of the process duration (1, 3, and 5h). The measured and calculated responses of osmotic dehydration process were: dry matter content, water loss, solid gain and the index of efficiency of the process. Test results shown that increase of the technological parameters of temperature and time of process, as well as the concentration of osmotic solutions lead to the intensification of mass transfer in the process and increase values of response parameters of the process. Also, it was concluded that during osmotic dehydration in sugar beet molasses cabbage was enriched with nutritional components, especially potassium. The third segment of this investigation was to analyze the viability of osmotically dehydrated cabbage packaged in modified atmosphere, with two different mixtures of N₂ and CO₂. Analyzing chemical, microbiological and sensory properties it was concluded that the osmotically dehydrated cabbage packaged in this manner has the sustainability of 90 days.</p>

<p>Hemometrijskim metodama (deskriptivna statistika, analiza glavnih komponenti, ve&scaron;tačke neuronske mreže i fazi optimizacija) analizirani su rezultati procesa osmotske dehidratacije mesa srebrnog kara&scaron;a, sa ciljem unapređenja efikasnosti osmotskog tretmana i pronalaženja optimalnih tehnolo&scaron;kih parametara.<br />Osmotski tretman se odvijao u tri osmotska rastvora (vodeni rastvor natrijum hlorida i<br />saharoze, kombinacija vodenog rastvora natrijum hlorida i saharoze i melase i melasa &scaron;ećerne repe) različitih koncentracija, na četiri temperature (10&deg;C, 20&deg;C, 35&deg;C i 50&deg;C) i pri tri vremena procesa (1, 3 i 5h). Posmatrani su sledeći odzivi sistema: gubitak vode, prira&scaron;taj suve materije, povećanje sadržaja suve materije, sniženje aktivnosti vode i promena sadržaja minerala (Na, K, Ca i Mg). Karakterizacijom osmotski dehidriranog ribljeg polupoizvoda, poja&scaron;njeni su efekti osmotskog tretmana i inovatinog osmotskog rastvora na senzorne osobine, hemijski i mikrobiolo&scaron;ki profil tretiranog mesa ribe. Rezultati ispitivanja pokazuju da se primenom procesa osmotske dehidratacije povećava gubitak vode, prira&scaron;taj suve materije i sadržaj suve materije u svim uzorcima mesa srebrnog kara&scaron;a. Za sva tri osmotska rastvora, najveće vrednosti dobijene su nakon 5 časova, pri najvi&scaron;im temperaturama i u najvećim koncentracijama rastvora.<br />Povećavanjem temperature procesa, koncentracije rastvora i vremena trajanja procesa, povećan je sadržaj posmatranih minerala u tretiranom mesu ribe. Rezultati<br />ANOVA testa pokazali su da na vrednosti posmatranih odziva statistički značajno utiču<br />sva tri parametra: vreme, temperatura i koncentracija. PCA analizom procesa utvrđeno je da su pri izračunavanju prve glavne komponente najveći uticaj imale vrednosti svih odziva osim aw vrednosti, dok je ona najvi&scaron;e uticala na proračun druge glavne komponente. Iako su modeli ve&scaron;tačkih neuronskih mreža kompleksniji od modela polinoma drugog reda, mreže su pokazale bolji učinak usled visoke<br />nelinearnosti razvijenih sistema. Primenom fazi optimizacije postignute optimalne vrednosti procesnih parametara za vodeni rastvor natrijum hlorida i saharoze su bile na nižim temperaturama i nižim koncentracijama rastvora, dok su za rastvore sa melasom &scaron;ećerne repe optimalne vrednosti na maksimumima posmatranih opsega temperature i koncentracije rastvora. Procesom osmotske dehidratacije smanjen je inicijalni broj bakterija u mesu srebrnog kara&scaron;a. Hemijskim i senzorskim analizama utvrđeno je da je melasa &scaron;ećerne repe zbog svog kompleksnog nutritivnog sastava<br />povoljnije je delovala na promenu hemijskog sastava i senzorne osobine uzoraka u odnosu na druga dva rastvora.</p> / <p>Chemometric methods (descriptive statistics, principal components analysis, artificial neural networks and fuzzy optimization) were used to analyze the results of osmotic dehydration of silver crucian carp, with the aim of improving the efficiency of the osmotic treatment and finding the optimal technological parameters.<br />The osmotic treatment was carried out in three osmotic solution (aqueous sodium chloride and sucrose solution, sugar beet molasses and the combination of these two solutions) of varying concentrations, at four temperatures (10&deg;C, 20&deg;C, 35&deg;C and 50&deg;C) and at three processing times (1, 3 and 5 h). The observed system responses were: water loss, solid gain, increase in dry matter content, reduction of water activity<br />and changes in mineral content (Na, K, Ca and Mg). The characterization of dehydrated fish, explained the effects of osmotic treatment on its sensory properties, chemical and microbiological profile. Results have shown that the application of osmotic dehydration increases water loss, solid gain and dry matter content in all samples of fish meat. For all three osmotic solution, the highest values were obtained after 5h, at the highest temperatures and in the highest concentration of the solution. By increasing the process temperature, concentration and time, increased the mineral content in the fish meat. The results of the ANOVA test have shown that the values of the observed responses significantly affect all three parameters: time, temperature and concentration. PCA analysis process has found that on calculation of the first principal component all response values except aw value had the greatest impact, while aw value had the most influence on the calculation of the other major component. Although models of artificial neural network models are more complex than second order polynomial, the network showed better performance due to the high nonlinearity of the developed system. Application of fuzzy optimization obtained optimal values of the process parameters for aqueous solution of sodium chloride and sucrose were at lower temperatures and lower concentrations of the solution, while the solutions with molasses optimal values of the maxima observed ranges<br />of temperature and solution concentration. The process of osmotic dehydration has reduced the initial number of bacteria in meat silver carp. Chemical and sensory analyzes have shown that the sugar beet molasses due to its complex nutritional composition has a better effect on changing the chemical composition and sensory characteristics of the samples.</p>

<p>Termalne osobine svinjskog mesa (Longissimus dorsi) osmotski dehidratisanog u melasi &scaron;ećerne repe i svežeg svinjskog mesa praćene su metodama termalne analize: Diferencijalnom skenirajućom kalorimetrijom (DSC), termogravimetrijskom analizom (TGA), modulovanom diferencijalnom skenirajućom kalorimetrijom (MDSC). Dobijeni rezultati pokazuju postojanje novonastale proteinske osnove osmotski dehidratisanog svinjskog mesa koji je posledica smanjenja količine vode i interakcije komponenti melase s proteinima mesa. Nađeno je da osmotskom dehidratacijom dolazi do promene i pregrupisavanja preostale slobodne vode u dva oblika, &scaron;to ukazuje na mehaničko strukturne promene u interfibrilarnoj mreži i pojednostavljivanje strukture proteinske osnove. Definisani su nastali strukturni nivoi proteinske osnove: strukturni nivo vode vezane na protein tj. postojanje proteinske strukture i posle osmotske dehidratacije -strukturni nivo I; strukturni nivo mreže sa ujednačeno manjim porama tj. nivo energetski jače vezane imobilizirane -strukturni nivo II; strukturni nivo mreže sa ujednačeno većim porama tj. nivo energetski slabije vezane imobilizirane -strukturni nivo III.<br />Ispitivanjem termalnih osobina uzoraka osmotski dehidratisanog mesa sa smanjenom vlagom ( ispod 20%) nađeno je postojanje staklastog prelaza po&scaron;to je najveća količina vode vezana za čvrsti matriks. Definisani su optimalni uslovi rehidratacije osmotski dehidratisanog svinjskog mesa, te su određene Pelegove konstante rehidratacije. Nađeno je postojanje nativnih struktura proteina u osmotski dehidtiranom mesu i određeni su kinetički parametri denaturacije (Ea, kb) svežeg i osmotski dehidriranog mesa. Određen je sadržaj makroelemenata osmotski su&scaron;enog svinjskog mesa. Radi obja&scaron;njenja složenosti interakcija proteina mesa i sastojaka osmotskog rastvora melase koje se odvijaju pri dehidrataciji, kao model sistem poslužila je interakcija proteina albumina goveđeg seruma (BSA) s jonima nekih makroelemenata prisutnih u melasi.</p> / <p>Thermal properties of pork meat (Longissimus dorsi) osmotically dehydrated in sugar beet molasses and fresh pork were followed by the methods of thermal analysis: Differential Scanning Calorimertry (DSC), Thermogravimetric Analysis (TGA), Modulated Differential Scanning Calorimetry (MDSC). The results indicate the existence of newly formed protein matrix as a consequence of osmotic dehydration of pork meat: reducing the amount of water and the interaction of the components of molasses and meat proteins. It has been found that changes were induced by the process of osmotic dehydration, and rearrangeement of the remaining free water in two forms. Also as a consequence of the osmotic dehydration, structural changes in the interfibrilar network and simplifying of the original structure of the meat protein matrix were occurred. A structural levels of protein matrix were defined: as structural level of the water bound to the protein, meaning the existence of protein structure and after osmotic dehydration Structural level I; a structural level with uniformly small pores in the network of formed protein matrix: energy level of more tightly immobilized water &ndash;Structural level II; and structural level of network with uniformly larger pores, energy level of lower bound immobilized water - Structural level III. By characterization of the thermal properties of the samples of osmotically dehydrated meat with reduced moisture (below 20%) the glass transition was found, as most of the water bound to a solid matrix.The optimal conditions for rehydration of dehydrated pork meat were defined, and Peleg&lsquo;s rehydration constants were obtained. It was found that the existence of the native structure of the protein in the osmotically dehydrated meat, and the kinetic parameters of protein denaturation (Ea, kb) of fresh and dehydrated meat were obtained. The content of macroelements in the osmotically dehydrated, fresh pork meat and in the sugar beet molasses were obtained. In order to explain the complexity of the interaction of meat proteins with the components of the osmotic solution -molasses that occur in the dehydration process, the model-system of the protein bovine serum albumin (BSA) interaction with the ions were implied to present simple interaction of some major elements with a protein matrix followed by DSC and ITC .</p>

The characterization of perphenazine and scopolamine aerosols generated using the capillary aerosol generator (CAG) was reported. Variables including steady state power, the formulation vehicle, the drug concentration and the formulation flow rate were studied for their effects on the chemical stability and particle size of these drug aerosols.Stability-indicating HPLC and LC-MS assays were developed and validated for perphenazine and scopolamine, respectively. The chemical stability of each compound was investigated under a variety of stress conditions and the structure of degradation products was proposed.Perphenazine aerosols were generated from propylene glycol (PG) formulations with concentrations of 9, 48 and 90mM at formulation flow rates of 2.5 and 5.0µL/s at a series of steady state powers. At higher aerosolization powers, the low concentration formulation (9mM) degraded with dehalogenation being the major pathway. The size of perphenazine aerosols was between 0.4 to 0.6µm. Changing the solute concentration produced only small changes (~0.2µm) in perphenazine aerosol particle size. The formulation flow rate did not significantly affect the aerosol size.Scopolamine degraded significantly when aerosolized in PG formulations. It was possible to generate chemically stable scopolamine aerosols from ethanol formulations. Significant amounts of degradation products were formed only at or above 4.6W at 5.0µL/s. Hydrolysis and dehydration appeared to be the major degradation pathways at higher powers and low formulation flow rate. The MMAD of scopolamine aerosols was between 0.5 and 2.0µm from 8, 20 and 40mM formulations at 5.0 and 10.0µL/s. The size of scopolamine aerosols increased as a function of increasing the solute concentration. Increasing the formulation flow rate increased the linear velocity of the spray, thus the Reynolds number was increased and smaller particles were generated.

Twelve halloysites from different sources in Slovakia, Turkey, China, New Zealand and U.S.A. have been characterized by combination of analytical methods together with the commercial sample of halloysite supplied by Sigma-Aldrich. The aim of this work was to select suitable candidates for to be used as carriers of porphyrine photoactive molecules. In nature, the formation of halloysite is related to the weathering of magmatic rocks or to the hydrothermal alteration of volcanic rocks, frequently in the contact with limestones. Halloysite belong to the kaolinite group, but, contrarily to kaolinite, it contains molecules of water in the interlayer space. It occurs in two forms: hydrated halloysite (10 ?) and dehydrated halloysite (7 ?).Dehydrated halloysites contain more admixtures than hydrated ones ? typically kaolinite, quartz, cristobalite, alunite, gibbsite and in one case also potassium mica. In samples containing both dehydrated halloysite and kaolinite their 001 diffractions overlap. Interaction with formamide was used in these cases to increase the interlayer space of halloysite and thus shift its basal diffraction to lower angles. The basal 001 diffraction of kaolinite after this treatment remains on 7 ?. Silver thiourea method (AgTU) was used to measure the cationic exchange capacity (CEC). Silver...

Le glycérol est valorisable par déshydratation en acroléine qui est un important intermédiaire chimique et peut être converti en une multitude de produits à valeur ajoutée dont l’acide acrylique qui est la base de nombreux polymères. Cette réaction est réalisée sur des catalyseurs acides comme les zéolithes protoniques qui donnent d’importants rendements initiaux en phase gazeuse (275-325°C) et à pression atmosphérique. Cependant, le principal inconvénient de ces matériaux est la désactivation rapide au cours du temps dû à la formation de dépôts carbonés appelés « coke ». L’ajout du fer sur les zéolithes H-BEA (larges pores) et H-MFI (pores moyens) a montré un effet fortement bénéfique sur cette réaction en présence d’air avec une formation supposée d’espèces actives qui permettraient de réduire de manière importante la désactivation du catalyseur et tout en favorisant la formation directe de l’acide acrylique sur la fonction métallique. Les zéolithes MFI au fer préparées par substitution isomorphe sont les plus performantes avec un rendement maximum en acide acrylique de 40% obtenu sur H-Fe3.8-Z-45 (préparé par synthèse hydrothermale). La zéolithe Np-Fe0.6-MFI-41 (préparé par traitement post-synthèse en milieu fluorure) permet d’obtenir un rendement en acroléine de plus de 80% après 24h de réaction, reproductible après régénération. Ce catalyseur est non seulement très actif, sélectif en acroléine, stable mais aussi régénérable, ce qui le place parmi les meilleurs pour ce procédé. / Glycerol is recoverable by dehydration into acrolein, which is an important chemical intermediate and can be converted into a variety of value-added products including acrylic acid that is the basis of many polymers. This reaction is carried out over acid catalysts, such as protonic zeolites which provide significant initial yields in the gas phase (275-325° C) and at atmospheric pressure. However, the main drawback of these materials is the rapid deactivation over time because of the formation of carbonaceous deposits known as "coke". The addition of iron over H-BEA (large pore) and H-MFI (mean pore) zeolites showed a highly beneficial effect on this reaction in the presence of air with an assumed formation of active species that would reduce significantly catalyst deactivation while promoting the direct formation of the acrylic acid on the metal function. H-MFI iron zeolites prepared by isomorphous substitution are the most efficient with a maximum acrylic acid yield of 40% obtained over H-Fe3.8-Z-45 (prepared by hydrothermal synthesis). Np-Fe0.6-MFI-41 zeolite (prepared by post-synthesis treatment in a fluoride medium) gives an acrolein yield of 80% after 24 hours of reaction, reproducible after regeneration. This catalyst is not only very active, selective to acrolein and stable but also regenerable, which places it among the best for this process.

När ett vävnadspreparat har genomgått en otillräcklig dehydrering måste det åtgärdas innan provet kan gå vidare i den histotekniska processen. I dagsläget finns det två åtgärdande metoder på Patologilaboratoriet, Region Jönköpings län. Den ena metoden går ut på att provet placeras i smält paraffin för mer stadga. Den andra metoden går ut på att provet rehydreras för att sedan dehydreras på nytt. Syftet med denna studie var att utvärdera en tredje metod, ”dumpingmetoden” som går ut på att vävnadspreparaten dehydreras på nytt direkt utan att först bli rehydrerade.  Denna metod utförs i nuläget redan på vissa hud- och obduktionspreparat på Patologilaboratoriet. ”Dumpingmetoden” skulle kunna förenkla arbetet på laboratoriet då den är snabbare, kräver färre kemikalier och är automatiserad till skillnad från befintliga metoder. Resultaten från studien visade att ett otillräckligt dehydrerat vävnadspreparat aldrig kan bli lika bra som om det hade hanterats korrekt från början. Det är dock trots allt möjligt att åtgärda ett otillräckligt dehydrerat preparat i den graden att det blir bedömbart. ”Dumpingmetoden” förenklade snittningen av alla preparat som testades. Hos kolon- och tonsillpreparat verkade ”dumpingmetoden” ge bättre kvalitet av hematoxylin- och eosinfärgningen än de befintliga metoderna. För hudpreparat gav dock metoden där vävnadspreparat rehydrerats för att sedan dehydreras på nytt bäst kvalité av infärgningen. / A tissue that has been insufficiently dehydrated has to be fixed before it can continue through the histotechnological process. Currently, there are two established measures at the Pathology Laboratory, Department of Laboratory Medicine, Region Jönköping County. One of the methods is to put the sample in melted paraffin to give the tissue more support. The other method is to rehydrate the tissue followed by a new dehydration. The purpose of this study was to evaluate a third method called the “dumping method”. The “dumping method” involves a directly dehydration of the tissue, excluding rehydration. This method is currently being used on some of the skin and autopsy samples at the Pathology Laboratory. The “dumping method” would ease the work at the Laboratory since it is faster, requires fewer chemicals and can be automated, unlike the current available methods. The results from the study showed that an insufficiently dehydrated tissue can’t be restore to its original state. Never less it is possible to restore the tissue sufficiently for diagnosis. The “dumping method” eased the sectioning of all the tissue samples included in this study. For colon and tonsil tissues, the “dumping method” ensured higher quality of the haematoxylin and eosin staining than the current available methods. For skin tissues, however, the method of rehydration followed by a new dehydration resulted in the highest staining quality

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho foram realizadas a cominuição e passivação da liga metálica U-4Zr-2Nb pelo processo de hidretação-desidretação, bem como o estudo da sua cinética. A obtenção deste material pulverizado através das técnicas da metalurgia do pó é uma etapa necessária e chave na fabricação da pastilha, que será empregada na laminação da placa combustível. Foi escolhida a liga com composição U-4Zr-2Nb devido à sua elevada densidade e baixo teor de elementos de liga, além de suas pequenas seções de choque para nêutrons térmicos. Previamente, foi projetado e construído o equipamento tipo Sievert volumétrico para a cominuição da liga metálica de urânio pelo processo de hidretação-desidretação, operacionalizando-o no modo automático, através da aquisição de dados por intermédio de softwares também desenvolvidos neste trabalho. Juntamente com o desenvolvimento deste equipamento, outro software foi desenvolvido para calcular a cinética de hidretração e a porcentagem hidretada. A seguir, com a utilização deste equipamento, amostras da liga U-4Zr-2Nb foram tratadas termicamente, hidretadas, passivadas, moídas e desidretadas. O processo de cominuição desenvolvido foi realizado nas condições de temperaturas de hidretação variando entre 108C e 295C e a pressão variando entre 2,0 bar e 1,5 bar. Todas as amostras foram hidretadas por completo, independentemente da temperatura de processamento. O tempo de hidretação variou entre 550 a 16176 segundos, de acordo com a temperatura utilizada, sendo mais rápido para temperaturas mais altas. Independentemente dos tratamentos térmicos feitos previamente nas amostras, todas apresentaram somente a fase &#945; e, conseqüentemente, todas as hidretações realizadas foram massivas. Foi desenvolvido também um processo de passivação dos pós obtidos, tendo-se conseguido amostras cominuídas estáveis, ou seja, não apresentaram reações pirofóricas quando expostas ao ar, nem uma excessiva oxidação das mesmas. Para isto, foi utilizada uma mistura de gases contendo 90% de argônio e 10% de oxigênio. Após a passivação, os hidretos foram moídos e passivados novamente para obtenção final do pó metálico. A granulometria final dos pós metálicos obtidos não depende dos tratamentos térmicos da amostra nem da temperatura de hidretação. As partículas maiores se revelaram um aglomerado de partículas menores e, portanto, foi utilizado um processo de moagem para desaglomeração parcial destas partículas, tendo-se obtidos partículas com tamanhos na faixa entre 11,2 e 22,4 &#956;m. / In this work the comminution and passivation of U-4Zr-2Nb alloys by hydrading-dehydrading process was carried out and the kinetics of hydride formation was studied. The obtaining of the powdered material through the techniques of powder metallurgy is a key and necessary step in the manufacture of the pellet useful for providing the fabrication of the fuel plate. An alloy with composition U-4Zr-2Nb was chosen due to their high density and low alloying elements, in addition to its low thermal neutrons cross section. A volumetric Sievert equipment for comminuition of uranium alloys by the process of hydriding-dehydriding was designed and constructed. This equipment operates in an automatic mode through the data acquisition software also developed in this work. Along with the development of this equipment, other software was developed to calculate the kinetic of hydriding and the hydriding amount. Then, using this equipment, samples of the U-4Zr-2Nb alloy were heat treated, hydrided, passivated, milled and dehydrided. The developed comminution process was obtained in the temperature range of 108oC to 295oC and in the pressure range of 1.5 Bar to 2 Bar. All samples were completely hydrided, regardless of the hydriding temperature. The hydriding time ranged from 540 to 16176 seconds, according to the temperature used, being faster at higher temperature. Regardless of the previously heat treatments, all samples showed only the &#945; phase and, consequently, all hydridings were massive performed. It was also developed a passivation process of the obtained powder, and the powdered samples were stable, not pyrophoric and no kind of reaction was observed when exposed to air, without an excessive oxidation. In this case, it was used a gas mixture of 90% argon and 10% oxygen. After passivation, the hydride were milled and passivated again to obtain the metallic powder. The final size of the powdered metal did not depend on the heat treatment of the sample or on the hydriding temperature. The larger particles revealed to be an agglomerate of particles and therefore the milling process partially dismantle these agglomerates into primary particles. The particles size ranged from 11.2 up to 22.4 &#956;m.

A solução salina hipertônica (SSH) é reconhecida por seu efeito ressuscitador em animais com choque hipovolêmico, aumentando a passagem de fluidos de outros órgão e tecidos para a corrente circulatória. Bovinos acometidos com acidose láctica ruminal aguda (ALRA) freqüentemente apresentam quadros de variável desidratação devido à passagem de fluidos do organismo para o rúmen, além do estabelecimento de acidose sistêmica, devido à absorção de ácido láctico ruminal. Como o SSH aumenta o volume de urina excretada seria plausível o efeito desta solução na excreção de íons H+ e lactato na urina de animais com ALRA. Doze bovinos machos, mestiços e de um ano de idade foram utilizados para avaliar o efeito do tratamento adicional de SSH sobre a (ALRA). Após período de adaptação e implantação de cânula no rúmen os animais foram submetidos à indução de ALRA por meio de quantidade calculada de sacarose administrada diretamente no rúmen. Após 20 horas da indução os animais foram aleatoriamente divididos em dois grupos iguais. Um deles (SSH) foi tratado com 5 mL/kg P.V. de uma solução de SSH a 7,5 %, dentro de 15 min, e 20 mL/kg/P.V. de solução salina isotônica (SSI) no decorrer dos próximos 165 minutos. Foram ainda retirados 5 L de conteúdo ruminal e adicionado igual quantidade de água no rúmen. O outro grupo (SSI) foi medicado da mesma forma, com exceção do SSH que foi substituído por 5 mL/kg PV de SSI. Variáveis foram mensuradas no momento 0 (MO), na 20 h (M20h) e no decorrer dos tratamentos com ISS ou SSH (M30´, M60´, M120´e M180´). Ao término desses tratamentos todos os animais foram medicados com quantidades calculadas de solução de 1,3 % de bicarbonato de sódio IV. A acidose ruminal obtida pela indução foi de grau médio a moderado, a acidose sistêmica e a intensidade de desidratação de graus moderados. A adição de água no rúmen nos primeiros 30 min. uma ligeira acidemia (0,03 graus de pH) acompanhada de discreta hipercapnia, além de gerar um aumento significativo na osmolalidade sérica favorecendo a absorção de fluidos do rúmen para a corrente sanguínea, avaliada pelo aumento de osmolalidade ruminal. Essa condição melhorou temporariamente o restabelecimento do volume globular. O tratamento com SSH ainda permitiu a maior excreção urinária, acompanhada de aumento da taxa de filtração glomerular e maiores eliminações de íons H+, lactato e fósforo. Existiu uma alta relação positiva entre a excreção de fósforo e pH urinários (R2= 0,562). O tratamento com SSH não gerou quaisquer reações colaterais. Os presentes resultados indicam que é vantajoso e adequado o tratamento de quadros de ALRA com SSH, em relação ao protocolo com SSI. / Hypertonic saline solution (HSS) is known by causing a resurrection effect in animals with hypovolemic shock, through the passage of fluids from other organs and tissues to the blood stream. Cattle with acute rumen lactic acidosis (ARLA) usually present different degrees of dehydration, caused by the migration of fluids from the body toward the rumen, besides the development of systemic acidosis by the absorption of ruminal lactic acid. As the HSS increases the volume of excreted urine would be plausible to suggest that this solution could enhance the urinary excretion of H+ and lactate in cattle with ARLA. Twelve yearling, cross-bred, male cattle were used to evaluate the effect of the additional treatment with HSS on cattle with ARLA. After an adaption period, when a rumen cannula was implanted, the animals were submitted to an induction of ARLA by a calculated amount of sucrose into the rumen. Twenty hours later the cattle were randomly divided in two equal groups. The 1st group was treated with 5 mL/kg BW with 7.5 % HSS, within 15 min, and 20 mL/ kg BW of isotonic saline solution (ISS) for the next 165 min. Five litres of rumen fluid was withdraw and equal volume of water was added into the rumen. The following group was treated equally, but the HSS that was changed to the same volume of ISS. Several variables were measured at different times of the experiment. At the end of this protocol all animals were treated with calculated amounts of 1.3% sodium bicarbonate solution IV. The induction caused a medium to moderate ruminal acidosis, and a moderate degree of systemic acidosis and dehydration. The administration of water caused a sharp decrease in the rumen osmolality. The treatment with HSS caused a mild academia (0.03 degree of pH) followed by a discrete hypercapnia, besides generating a significant increase in the serum osmolality, which favours the rumen fluid absorption into the blood stream. This condition improved temporarily the recovering of globular volume. The treatment with HSS also increased the urinary volume excreted followed by the improvement of the glomerular filtration ratio and the global excretion of H+, lactate and phosphorus. A high positive relationship was found between the excretion of urinary phosphorus and urine pH (R2 = 0,562). No side effects were seen in cattle treated with HSS. The present results show that is beneficial and adequate the treatment of ARLA with HSS, as compared to the protocol with ISS.