The events of cardiac surgery combined with moderate hypothermia hemodilution perfusion and postoperative respiratory care provide the stimuli for the alteration of K+ levels in red blood cells, plasma, and urine. The purpose of this study was to measure the deviations from normal potassium ion concentrations in an attempt to understand the physiological processes involved.

This project aims to evaluate the technical feasibility of an absorption process for carbon capture and storage (CCS). Currently, the CCS process commonly used in the industry is energy and cost-intensive, making its large-scale development a difficult task. The process under evaluation in this project is labeled as an intensified CCS process as it is more energy-efficient, theoretically, compared to the current standard process. The intensified process is based on absorption with aqueous K2CO3/KHCO3 followed by cristallization of KHCO3. The project aims to show the technical feasibility of two parts of the intensified process, the cooling crystallization in the reactor and the regeneration of carbon dioxide through calcination. The cooling crystallization was conducted at different cooling rates for two different solution compositions, while the calcination was conducted the same for all tests. Microscopic images were utilized to examine the relationship between cooling rates, solution composition, crystal size, and clustering. Thermogravimetric analysis was used to simulate the calcination and to analyze the crystals' decomposition and purity. The report concludes that none clustered selective crystallization of potassium bicarbonate and the total regeneration of carbon dioxide through calcination were achieved. A conclusive correlation between cooling rates and crystal yields could not be proven. And the relationship between crystal size and cooling rates substantially deviated from what was expected. Based on the results the intensified process is deemed technically feasible. / Syftet med detta projekt är att utvärdera den tekniska genomförbarheten av en “carbon capture and storage” (CCS) absorptionsprocess. CCS-processen som nuvarande förekommer i industrin är både energi- och kostnadskrävande, detta förhindrar möjligheten till vidare uppskalning. Processen som utvärderas i detta projekt kallas för en intensifierad CCS-process vilket innebär att den är teoretiskt mer energieffektiv jämfört med nuvarande standardprocess. Den intensifierade processen är baserad på absorption med en K2CO3/KHCO3 vattenlösning följt av en kristallisation av KHCO3. Projektet ämnar att visa den tekniska genomförbarheten av specifikt två delar av den intensifierade processen, kylningskristalliseringen i reaktorn samt regenereringen av koldioxid genom kalcinering. Kylningskristalliseringen genomfördes med olika kylningshastigheter för två olika lösningskompositioner medan kalcineringen utfördes likadant för samtliga tester. Mikroskopiska bilder nyttjades för att undersöka förhållandet mellan kylningshastigheten, lösningens sammansättning, kristallstorlek och kristallkluster. Termogravimetrisk analys användes för att efterlikna kalcineringen samt analysera kristallernas sönderdelning och renhet. Rapporten fastställer att selektiv kristallisering av kaliumbikarbonat uppnåddes utan signifikant kluster. En definitiv korrelation mellan kylningshastighet och kristallutbyte kunde ej påvisas. Förhållandet mellan kristallstorlek och kylningshastighet avvek betydande från vad som förväntades. Baserat på resultaten bedömdes den intensifierade processen vara tekniskt genomförbar.

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Yes / In this work, adsorption desulfurization is considered for making cleaner fuel. New efficient adsorbents have been designed by using two active metal oxides mainly potassium permanganate (KMnO4) and potassium phosphate (KPO4·3H2O) on Activated Carbon (AC). Ultrasonic assisted impregnation method (IWI) is used in designing the adsorbents offering high pore volume, pore size, surface chemistry, and high surface area. Use of ultrasonic method increases the dispersion of the active material (groups) on AC leading to increased number of collisions between O-atom on AC-support resulting in high sulfur removal from fuel. KMnO4 on AC shows higher adsorption capacity towards sulfur than KPO4·3H2O at the same operating conditions. New results with respect to sulfur removal has obtained compared with those obtained by previous studies. Finally, the adsorption kinetic parameters of such process are developed. Thomas and Yoon-Nelson models and the experimental data are used for this purpose using linear and non-linear regression analysis. Yoon-Nelson kinetic model fits well with the experiments data better than Thomas kinetic model in the entire adsorption column system.

Ce mémoire porte sur l'étude d'une variante d'épissage du cotransporteur humain cation-chlore orphelin (huCCC9a), un membre de la superfamille des cotransporteurs cation-chlore qui compte neuf membres, CCC1 à 7 qui ont pour fonction de transporter les ions Na+ et/ou K+ avec le Cl" à travers les surfaces cellulaires, et CCC8 et 9, dont les substrats ioniques demeurent inconnus à ce jour. Nous avons découvert que huCCC9, bien qu'il appartienne à la famille des CCCs, fait partie d'un groupe plus large de protéines appelé « famille des transporteurs d'acides aminés-polyamines-organocations » (ou APC pour l'acronyme anglais amino acid-polyamine-organocation transporter s). Nous avons donc voulu savoir si huCCC9a est impliqué dans le mouvement transmembranaire (tm) des polyamines d'autant plus que la plupart des cellules animales semblent être capable de promouvoir le transport facilité de tels substrats sans que la nature moléculaire exacte des protéines responsables, contrairement aux organismes unicellulaires, ait pu être déchiffrée. Nos résultats ont montré que huCCC9 permettait le transport de la spermidine > spermine > putrescine. De plus, nous avons aussi trouvé que l'influx de polyamines par CCC9a est augmenté en présence de certains acides aminés, que cet influx est indépendant des ions Na+ , K+ et Cl" et qu'il est inhibé par le furosémide et la pentamidine. Ces résultats revêtent une importance capitale en ce qu'ils correspondent à la première identification faite à ce jour d'un transporteur de polyamine chez les cellules animales et en ce sens qu'il semble exister un lien important entre le métabolisme intracellulaire des polyamines et la carcinogenèse de même qu'entre le gène CCC9a et une maladie appelée psoriasis vulgaris. / Cation-Cl" transporters (CCCs) belong to a large family of proteins that includes nine isoforms: CCC1 to 7, which have been shown to promote Cl" movement along with Na+ and/or K+ movement across cell surfaces, and CCC8 and 9, which have not been ascribed a specific transport function yet. The CCCs are also part of a larger family of proteins that are regrouped under the name amino acid-polyamine-organocation carriers (APC). In contrast to the CCCs, however, proteins involved in polyamine transport have only been isolated from unicellular species and do not necessarily belong to the APC family. In this work, we have found that a splice variant of CCC9 (called CCC9a) probably operates as one such polyamine transporter in higher species given that its expression in HEK-293 cells increases the influx of spermidine > spermine > putrescine at the cell surface and that it is otherwise widely distributed in certain mammals. We have also found that the influx of PAs by CCC9a increases further in the presence of certain amino acids, is Na+ -K+ -Cl"-independent and is inhibited by furosemide and pentamidine. Hence, a group of substrates that are transported by CCC9 as well as the molecular identity of a PA transport System in animal cells have been uncovered through this work for the first lime. These findings are of special interest given that CCC9 has been linked to the development of psoriasis vulgaris in the population and that intracellular PAs play a key role in cellular proliferation.

No / Rapid exposure of cardiac muscle to high concentrations of caffeine releases Ca 2+ from the sarcoplasmic reticulum (SR). This Ca 2+ is then extruded from the cell by the Na +/Ca 2+ exchanger. Measurement of the current carried by the exchanger ( I Na/Ca) can therefore be used to estimate of the Ca 2+ content of the SR. Previous studies have shown that caffeine, however, can also inhibit K + currents. We therefore investigated whether the inhibitory effects of caffeine on these currents could contaminate measurements of I Na/Ca. Caffeine caused partial inhibition of the inward rectifier K + current ( I K1): the outward current at ¿40 mV was 1.15±0.24 pA/pF in control and decreased to 0.34±0.15 pA/pF in the presence of 10 mmol/l caffeine ( P<0.05, n=15). This was similar to the effect of caffeine on the holding current observed at ¿40 mV in the absence of K + channel block and could therefore account for the contaminating effects of caffeine observed during measurements of I Na/Ca. Moreover, caffeine also partially inhibited the transient outward ( I to) and the delayed rectifier ( I K) K + currents.

Made available in DSpace on 2017-07-10T17:37:36Z (GMT). No. of bitstreams: 1 Fabio_Steiner.pdf: 1984237 bytes, checksum: dd7fb075cef8a63a4698725e6595b0ed (MD5) Previous issue date: 2010-02-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Potassium uptake by plants, in general, is greater than the initial amount of exchangeable K, indicating that non-exchangeable participate in supplying this nutrient to plants. Thus, this study aimed (a) determine the forms of K total, non-exchangeable K, exchangeable K and K in soil solution, (b) determine the buffering capacity of soil potassium, (c) evaluate the ability of potassium supply native and added to a succession of crops, and (d) evaluate the contribution of different forms of potassium in the soil to supply a succession of crops. In this study two experiments were conducted in a greenhouse at the Center for Agricultural Sciences, State University of West Parana, Marechal Candido Rondon, PR, from October 2008 to november 2009. Surface samples (0-20 cm) of 12 soils collected from different regions of Parana State, were subjected to the addition or not of potassium fertilizer (KCl) and the six successive crops (soy, millet, wheat, beans, soybeans and corn). Plants were grown until approximately 40 days after emergence and determined the dry matter production and K content of In the initial samples and those collected after the second, fourth and sixth batch were certain forms of K total, non-exchangeable, exchangeable and soil solution. The forms of soil K showed a large range of values depending on the source material and the degree of weathering of the soil. Soil texture affected the buffering capacity of potassium (PTK), which presented values between 1.28 and 12.79 (mmolc kg-1)/(mmol L-1)0.5. The soils differed in the ability to supply K to the crops, with an important contribution of non-exchangeable forms in the six crops that ranged from 0 to 17.7% with addition of potassium fertilizer and 44.1% to 72.9% without the addition of potassium fertilizer. After the second crop contents of exchangeable K remained constant with average values of 141 and 36 mg kg-1, with and without the addition of potassium fertilizer, respectively / A absorção de K pelas plantas, em geral, e maior que a quantidade inicial de K trocável, indicando que formas não-trocáveis contribuem no suprimento deste nutriente as plantas. Assim, o presente trabalho teve como objetivos (a) determinar as formas de K total, K não-trocável, K trocável e K na solução do solo; (b) determinar o poder tampão de potássio dos solos; (c) avaliar a capacidade de suprimento de potássio nativo e adicionado a uma sucessão de cultivos; e (d) avaliar a contribuição das diferentes formas de potássio do solo no suprimento a uma sucessão de cultivos. Neste estudo foram conduzidos dois ensaios em casa de vegetação no Centro de Ciências Agrárias da Universidade Estadual do Oeste do Paraná, Marechal Candido Rondon, PR, no período de outubro de 2008 a novembro de 2009. Amostras superficiais (0 20 cm) de 12 solos coletadas em diferentes regiões do Estado do Paraná, foram submetidas a adição ou não de fertilizante potássico (KCl) e a seis cultivos sucessivos (soja, milheto, trigo, feijão, soja e milho). As plantas foram cultivadas ate aproximadamente 40 dias apos a emergência, sendo determinada a produção de matéria seca e o teor de K. Nas amostras iniciais e naquelas coletadas apos o segundo, quarto e sexto cultivo foram determinadas as formas de K total, não-trocável, trocável e na solução do solo. As formas de K do solo apresentaram grande amplitude de valores em função do material de origem e do grau de intemperismo do solo. A textura do solo influenciou o poder tampão de potássio (PTK) que apresentou valores entre 1,28 e 12,79 (mmolc kg-1)/(mmol L-1)0,5. Os solos se diferenciaram na capacidade de suprimento de K aos cultivos, havendo uma contribuição importante de formas não trocáveis durante os seis cultivos que variou de 0 a 17,7% com adição de fertilizante potássico e de 44,1% a 72,9% sem adição de fertilizante potássico. Após o segundo cultivo os teores de K trocável mantiveram-se constantes com valores médios de 141 e 36 mg kg-1, com e sem a adição de fertilizante potássico, respectivamente

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.

KCNQ1 is a homotetrameric voltage-gated potassium channel expressed in cardiomyocytes and epithelial tissues. However, currents arising from KCNQ1 have never been physiologically observed. KCNQ1 is able to provide the diverse potassium conductances required by these distinct cell types through coassembly with and modulation by type I transmembrane β-subunits of the KCNE gene family. KCNQ1-KCNE K+ channels play important physiological roles. In cardiac tissues the association of KCNQ1 with KCNE1 gives rise to IKs, the slow delayed outwardly rectifying potassium current. IKs is in part responsible for repolarizing heart muscle, and is therefore crucial in maintaining normal heart rhymicity. IKschannels help terminate each action potential and provide cardiac repolarization reserve. As such, mutations in either subunit can lead to Romano-Ward Syndrome or Jervell and Lange-Nielsen Syndrome, two forms of Q-T prolongation. In epithelial cells, KCNQ1-KCNE1, KCNQ1-KCNE2 and KCNQ1-KCNE3 give rise to potassium currents required for potassium recycling and secretion. These functions arise because the biophysical properties of KCNQ1 are always dramatically altered by KCNE co-expression. We wanted to understand how KCNE peptides are able to modulate KCNQ1. In Chapter II, we produce partial truncations of KCNE3 and demonstrate the transmembrane domain is necessary and sufficient for both assembly with and modulation of KCNQ1. Comparing these results with published results obtained from chimeric KCNE peptides and partial deletion mutants of KCNE1, we propose a bipartite modulation residing in KCNE peptides. Transmembrane modulation is either active (KCNE3) or permissive (KCNE1). Active transmembrane KCNE modulation masks juxtamembranous C-terminal modulation of KCNQ1, while permissive modulation allows C-terminal modulation of KCNQ1 to express. We test our hypothesis, and demonstrate C-terminal Long QT point mutants in KCNE1 can be masked by active trasnsmembrane modulation. Having confirmed the importance the C-terminus of KCNE1, we continue with two projects designed to elucidate KCNE1 C-terminal structure. In Chapter III we conduct an alanine-perturbation scan within the C-terminus. C-terminal KCNE1 alanine point mutations result in changes in the free energy for the KCNQ1-KCNE1 channel complex. High-impact point mutants cluster in an arrangement consistent with an alphahelical secondary structure, "kinked" by a single proline residue. In Chapter IV, we use oxidant-mediated disulfide bond formation between non-native cysteine residues to demonstrate amino acid side chains residing within the C-terminal domain of KCNE1 are close and juxtaposed to amino acid side chains on the cytoplasmic face of the KCNQ1 pore domain. Many of the amino acids identified as high impact through alanine perturbation correspond with residues identified as able to form disulfide bonds with KCNQ1. Taken together, we demonstrate that the interaction between the C-terminus of KCNE1 and the pore domain of KCNQ1 is required for the proper modulation of KCNQ1 by KCNE1, and by extension, normal IKs function and heart rhymicity.

LD2668 .T4 1947 K4 / Master of Science