Dissertations / Theses: 'Na+/Ca2+ exchanger'

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Parnis, Julia [Verfasser]. "The physiological role of mitochondrial Na+/Ca2+ exchanger NCLX for glial Ca2+ homeostasis / Julia Parnis." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2013. http://d-nb.info/1031099506/34.

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Zhao, Jun, and e52677@ems rmit edu au. "The functional study of Na+/Ca2+ exchanger in vascular smooth muscle cells." RMIT University. Medical Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080617.163746.

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Na+/Ca2+ exchanger (NCX) is a membrane protein which can mediate either Ca2+ entry (reverse mode) or exit (forward mode) in cells. As one of the major Ca2+ transport systems, NCX is postulated to play a critical role in the vascular smooth muscle cell. The aims of the present study are to firstly demonstrate the functional existence of NCX in vascular smooth muscle (including aorta and arteriole); to clarify the modulation of NCX; to explore the selectivity of NCX inhibitor KB-R7943; and lastly to investigate the role of NCX in the myogenic response. KB-R7943 has been widely used as a NCX inhibitor. The study investigated its pharmacological actions in rat aorta on a variety of Ca2+ dependent systems. Rat aortic rings were used. The constriction to low extracellular [Na+] is a functional response mediated by NCX operating in reverse mode. The data demonstrate that 10 µM KB-R7943 inhibited L-type Ca2+ channel, the capacitative Ca2+ entry and  adrenergic receptor pathway. Nevertheless, KB-R7943 can be used as a selective inhibitor of NCX at the lower concentration of 1 µM in rat aortic rings. The study investigated whether the endothelium could modulate NCX in rat aortic rings. Lowering extracellular [Na+] to 1.18 mM induced constriction in endothelium denuded rat aortic rings, but only a small constriction in endothelium intact rat aortic rings. In endothelium intact rat aortic rings, the guanylate cyclise inhibitor ODQ (1 µM) and the nitric oxide synthase inhibitor L-NAME (50 µM) greatly amplified the vasoconstriction to lowering extracellular [Na+], but had no effect when the endothelium was removed. The adenylate cyclise inhibitor SQ 22536 (100 µM) and the cyclooxygenase inhibitor indomethacin (10 M) showed no significant effect on the low-Na+ induced vasoconstriction in either endothelium denuded or intact aortic rings. The results suggest that endothelium modulated the NCX operation via the nitric oxide/guanylate cyclase, not the adenylate cyclase system; further prostanoids including prostacyclin was not involved. The interaction between nitric oxide and NCX was furt her explored using the nitric oxide donor sodium nitroprusside. Endothelium denuded rat aortic rings were preconstricted to the same extent with either low Na+ (1.18 mM), or the thromboxane A2 agonist U46619 (0.1 µM) or high K+ (80 mM). The vasorelaxation of SNP (30 nM) in low Na+ constriction was significantly larger compared to other agents. This indicates that NO has a special antagonism of low Na+ constriction and a hypothesis is proposed involving Na+/K+ ATPase. The investigation of NCX is mainly conducted in large vessels; much less evidence is available for small resistance vessels. The study investigated the role of NCX on myogenic response in pressurized cremaster muscle arterioles. Reducing extracellular [Na+] resulted in graded vasoconstriction which was inhibited by NCX inhibitor SEA0400 (1 µM). Myogenic vasoconstriction and the concomitant rise in internal [Ca2+] were induced by a transmural pressure increase from 70 to 120 mmHg which was prevented by NCX inhibitor: SEA0400 (1 µM). In conclusion, the present study suggests that NCX contributes to the myogenic response in cremaster arteriole.

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PRITCHARD, TRACY J. "Expression and Function of the Na ⁺-K ⁺ATPase α-Isoforms in Smooth Muscle: Evidence from Transgenic Mice." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1186672962.

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Barman, Palash Pratim. "β-adrenoceptor/protein kinase A modulation of rabbit cardiac Na+-Ca2+ exchanger and cystic fibrosis transmembrane conductance regulator." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617927.

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The Na2+-Ca2+ Exchanger (NCX), all important Ca2+ handling plasmalemmal protein, is expressed widely in cardiac tissues and plays important roles in physiological and pathophysiological cardiac function . A key aim of this study was to determine whether or not B-adrenoceptor/PKA stimulation modulates NCX current (lNCX), measured as Ni2+ sensitive current, independent of potential contamination from a PKA-activated CI current (lCIPKA), encoded by the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) channel. Pharmacological effects of a 'selective' CTFR blocker, GyH-101 were also tested. Additional work was also conducted on human atrial INCX and NCX expression. Methods: Rabbit ventricular and atrial and human atrial myocytes were used in whole-cell patch-clamp experiments at 37°C. Selective conditions for NCX and CI currents were used as appropriate. NCX protein was measured by Western Blotting. Results and conclusions: Under NCX•selective recording conditions 10 mM Ni2+ blocked isoprenaline activated current, but the Nil+• sensitive ventricular INcx activated by forskolin was similar to that in control. In rabbit atrial tissues, which lack ICLPKA, forskolin did not increase the Ni2-•sensitive current component. External but not internal Ni 21 inhibited lc1PKA, with a sub• millimolar IC50, when this was activated by isoprenaline but not forskolin suggestive of a Nil+ action upstream to adenylyl cyclase, likely directly on the B1• adrenoceptor. Thus, the apparent increase rabbit ventricular INt:x with isoprenaline in NCX recording conditions is likely to be attributable to overlapping Ni2+•sensitivc IctPKA, rather than INCX activation by B-adrenoceptor/PKA stimulation. The CFTR inhibitor GlyH•-1Ol produced voltage• dependent inhibition of cardiac IC1PKA, but additionally also inhibited I and IKI . Consequently this compound is not entirely CFTR•selective in respect of cardiac electrophysiology. Human atrial INt:x density and its current voltage relationship were very similar to those of rabbit atrial myocytes. In the human atrial samples examined, there was no significant difference in NCX protein expression between patients in sinus rhythm and those in chronic atrial fibrillation.

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Nakamura, Toshio. "Expression of the Na+/Ca2+ exchanger emerges in hepatic stellate cells after activation in association with liver fibrosis." Kyoto University, 1998. http://hdl.handle.net/2433/182267.

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Stabelini, Tatiana Comporte. "Estudos estruturais de fragmentos do trocador de Na+/Ca2+ por RMN em solução." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-11122018-091550/.

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Proteínas de membrana estão envolvidas em processos fisiológicos essenciais como, por exemplo, a manutenção do equilíbrio iônico e sinalização intracelular. No entanto, apesar do envolvimento em inúmeros processos fisiológicos e de grande interesse farmacêutico, o estudo estrutural de proteínas de membrana ainda é um processo custoso e muito mais complexo do que o estudo estrutural de proteínas solúveis. Os trocadores de Na+/Ca2+ são proteínas de membrana que atuam na manutenção da homeostase de Ca2+ intracelular e estão envolvidos em processos patológicos como doenças cardíacas. Estes trocadores estão presentes em diversas espécies de mamíferos (NCX) e insetos, por exemplo, na mosca Drosophila melanogaster (CALX). A topologia destas proteínas é constituída de dois domínios. O domínio transmembranar, que contém dois segmentos de 5 hélices transmembranares (TMH) e é responsável por promover o transporte específico de íons Ca2+ e Na+ através da membrana, e o domínio citoplasmático, responsável por regular a atividade do trocador. O domínio citoplasmático consiste de uma alça que contém dois domínios sensores de Ca2+ intracelular (CBD1 e CBD2). Trabalhos mostraram que o trocador CALX é inibido pela ligação de Ca em CBD1, enquanto que trocadores NCX são ativados. As regiões citosólicas que conectam CBD1 e CBD2 à TMH5 e TMH6 são conservadas e ainda não foram caracterizadas estruturalmente. Adjacente à TMH5 há um segmento anfipático, denominado exchanger inhibitory peptide (XIP), que está envolvido no mecanismo de regulação do trocador. Na ausência de dados estruturais do CALX completo, o estudo de TMH5-XIP poderá aumentar a compreensão sobre a estrutura e o funcionamento do trocador. A construção TMH5-XIP foi fusionada à MBP no N-terminal e a uma sequência de 8 histidinas no C-terminal. Apesar da expressão da proteína de fusão ter sido bem sucedida, problemas de precipitação e ineficiência durante a clivagem da conexão com a MBP impediram a conclusão dos estudos estruturais. Logo, uma construção menor, contendo apenas a região equivalente ao XIP, foi estudada por espectroscopia de RMN em solução e dicroísmo circular. XIP forma uma 310-hélice a baixa temperatura, 7 oC, que se desestabiliza a maior temperatura, 27 oC. Estes dados permitem a formulação de hipóteses sobre o papel de XIP no mecanismo de regulação do domínio transmembranar de CALX.
Membrane proteins are involved in essential physiological processes such as maintenance of the ionic balance and intracellular signaling. However, despite their role in numerous physiological processes of well-recognized pharmaceutical relevance, structural studies of membrane proteins remain being more complex than structural studies of globular proteins. Na+/Ca2+ exchangers (NCX) are membrane proteins that play essential roles in the maintenance of the intracellular Ca2+ homeostasis. Not surprisingly, the NCXs are involved in pathologies such as heart diseases. These exchangers are present in several species of mammals (NCX) and insects, for example, in the fly Drosophila melanogaster (CALX). The topology of these proteins consists of a transmembrane and a hydrophilic domain. The transmembrane domain corresponds to two segments of 5 transmembrane helices (TMH) forming a 10-helix bundle that is responsible for the specific transport of Ca2+ and Na+ across the cellular membrane. The hydrophilic domain is composed of a large cytoplasmic loop, which is associated with the regulation of the ion exchange activity of the transmembrane domain. The loop contains two Ca2+-sensors domains, CBD1 and CBD2, and uncharacterized regions. Studies showed that Ca2+ binding to CBD1 inhibits the CALX, whereas it activates the NCX. The juxtamembrane cytosolic regions linking the CBD1 and CBD2 domains to the TMH5 and TMH6, respectively, are highly conserved but have not yet been structurally characterized. The segment near TMH5 is amphipathic, and it is also called exchanger inhibitory peptide (XIP). In the absence of a three-dimensional structure of the complete CALX, the study of TMH5-XIP may contribute to our understanding of the structure and operation of the exchanger. In order to study TMH5-XIP, it was fused to an MBP tag at the N-terminus, and to a sequence of 8 histidines at the C-terminus. Although the expression of the fusion protein was successful, precipitation and inefficient MBP-tag cleavage prevented the isolation of pure TMH5-XIP for structural studies. Hence, a smaller construct, containing only the region equivalent to XIP, was studied by NMR spectroscopy in solution and circular dichroism. The structure assumed by XIP in solution is temperature dependent, being intrinsically disordered at 27 C or a 310-helix at 7 C, respectively. These findings allowed us to infer how XIP could participate in the CALX regulation mechanism.

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PICCIRILLO, SILVIA. "Involvement of Na+/Ca2+ Exchanger (NCX) in Glutamate-Induced Neuroprotection in SH-SY5Y Differentiated Cells Subjected to Hypoxia/Reoxygenation (H/R) Injury." Doctoral thesis, Università Politecnica delle Marche, 2019. http://hdl.handle.net/11566/263512.

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L’ischemia cerebrale è una patologia caratterizzata dalla ridotta o totale assenza di ossigeno e di substrati metabolici che influiscono sulla respirazione aerobia determinando un danno mitocondriale in particolare nella sintesi di ATP e nello squilibrio ionico culminando nella morte cellulare. L’entità del danno non deriva solo dall’insulto ischemico ma anche dai successivi fenomeni deleteri stimolati dal ripristino del flusso sanguigno e dei livelli di ossigeno. Lo squilibrio metabolico cerebrale induce l’utilizzo di fonti energetiche alternative come il glutammato. Sebbene in passato il glutammato è sempre stato considerato neurotossico, recenti studi hanno evidenziato come il glutammato possa svolgere il ruolo di intermediario metabolico stimolando la sintesi di ATP e migliorando l’attività mitocondriale, grazie al ruolo essenziale svolto dallo scambiatore Na+ /Ca2+ (NCX) e dai trasportatori del glutammato Na+ dipendenti (EAATs). In particolare, il ruolo solto da NCX nella neuroprotezione indotta da glutammato è stato studiato utilizzando un modello in vitro di ischemia cerebrale, cellule di neuroblastoma umano SH-SY5Y differenziate sottoposte ad ipossia/reossigenazione (H/R). In questo modello il danno indotto da H/R determina un aumento della mortalità cellulare, una riduzione dei livelli intracellulari di ATP e un’alterazione dei livelli di Ca2+ intracellulare. L’aggiunta di glutammato all’inizio della fase di reossigenazione determina un parziale recupero del danno inducendo un significativo aumento dei livelli di ATP. Inoltre, l’aggiunta di glutammato recupera parzialmente la riduzione dell’attività reverse-mode di NCX indotto da H/R. La trasfezione con i siRNA diretti contro NCX1 ed EAAT3 bloccano gli effetti protettivi del glutammato, confermando il ruolo essenziale svolto da NCX ed EAAT3 in questo pathway. In conclusione, i risultati ottenuti mostrano un nuovo ruolo svolto dal glutammato come “fattore di sopravvivenza” nel miglioramento del danno indotto da ipossia/reossigenazione, e che l’interazione tra NCX1 ed EAAT3 è fondamentale per permettere al glutammato di esplicare la sua funzione neuroprotettiva.
In brain ischemia, reduction of oxygen and substrates affects mitochondrial respiratory chain and aerobic metabolism culminating in ATP production impairment, ionic derangement and cell death. An exacerbation of the tissue damage frequently occurs during the restoration of blood flow and reoxygenation, giving rise to ischemia/reperfusion (I/R) injury. Energy dysfunction in cerebral metabolism may induce the utilization of alternative energy supplies, such as glutamate. Although glutamate has long been considered as a neurotoxin, it can also be used as a metabolic intermediate for the ATP synthesis thus improving mitochondrial activity. In this setting, both the Na+/Ca2+ exchanger (NCX) and the Na+ dependent Excitatory Amino Acid Transporters (EAATs) play a critical role. The aim of the present study is to investigate the role of NCX in the potential of glutamate to improve cell metabolism and survival of neuronal cells subjected to hypoxia/reoxygenation (H/R) injury. In SH-SY5Y neuroblastoma cells differentiated into neuron-like cells, H/R produced a significant cell damage, a drop of ATP cellular content and intracellular Ca2+ alterations. Exposure to glutamate at the onset of the reoxygenation phase induces an improvement of cell survival and a significant raise in intracellular ATP levels by stimulating mitochondrial oxidative phosphorylation. Furthermore, NCX reverse-mode is reduced in H/R cells and glutamate supplementation limits the H/R induced suppression of NCX activity. All the effects induced by glutamate exposure are lost when cells are transfected with small interfering RNA (siRNA) against NCX1 and EAAT3, suggesting that a functional interplay between these proteins is critically required for glutamate neuroprotection. Collectively, our results reveal the beneficial effect of glutamate in an in vitro model of H/R injury and focus on the essential role exerted by NCX1.

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Hammann, Jens [Verfasser]. "Influence of Na+, K+-ATPase and Na+/Ca2+ exchanger on developmental ion signaling and MBP synthesis in murine oligodendrocyte precursor cells / Jens Hammann." Mainz : Universitätsbibliothek Mainz, 2018. http://d-nb.info/1163416274/34.

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Al, Maghout Tamer [Verfasser]. "P38 Kinase, SGK1 and NF-κB Dependent Up-Regulation of Na+/Ca2+ Exchanger Expression and Activity Following TGFß1 Treatment of Megakaryocytes / Tamer Al Maghout." Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1221596780/34.

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ALEMANNI, MATTEO. "The modulation of SERCA pump activity as a tool for management of hearth failure." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7462.

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The current positive inotropic interventions for the management of heart failure (HF) are all associated to an unchanged or increased long term mortality, which limit their use. Istaroxime (IST) is a novel positive inotrope able to inhibit Na+, K+ ATPase and to stimulate SERCA pump. We employed IST as a tool to assess the role of a mild SERCA stimulation as a positive inotropic intervention. In a guinea pig model of HF, where the sarcoplasmic reticulum (SR) function was deranged, IST was able to restore an optimal SR function, increase the SR Ca2+ content and to improve all the EC coupling parameters considered. The comparison if IST and digoxin, a pure inhibitor of Na+, K+ ATPase, in mouse ventricular myocytes, showed that IST was less pro-arrhythmic than digoxin, as already observed in guinea pig. Digoxin induced a rapid accumulation of cytosolic Ca2+, while IST did not, and neither compound directly affected SR Ca2+ leakage, suggesting that a better compartmentalization of the ion was achieved in the presence of IST by the stimulation of SERCA pump. We concluded that the mild stimulation of SERCA is associated to a reduced pro-arrhythmic effect, and that it might represent a promising target for a new class of positive inotropic interventions associated to a reduced long term mortality.

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Abiko, Layara Akemi. "Estudo da dinâmica funcional dos domínios regulatórios do trocador de Na+/Ca2+ de Drosophila melanogaster por ressonância magnética nuclear em solução." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-20072015-115123/.

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O trocador de Na+/Ca2+ (NCX) constitui um dos principais mecanismos de extrusão de Ca2+ intracelular em células excitáveis. Foi demonstrado que alterações no funcionamento do NCX estão relacionadas a diversas situações patológicas. Por este motivo, o entendimento do mecanismo molecular da manutenção da concentração de Ca2+ intracelular via NCX é importante para a compreensão do funcionamento do trocador, bem como para o desenvolvimento de fármacos. Além de transportar Na+/Ca2+, o NCX também é regulado por esses íons. Este trocador é composto por dois domínios transmembranares, cada um deles contendo 5 α-hélices (TM), e uma grande alça intracelular que conecta as hélices TM5 e TM6. O domínio transmembranar é responsável por catalisar o transporte de Na+/Ca2+ através da bicamada lipídica, enquanto que a alça citoplasmática está envolvida com a regulação do trocador. Esta alça contém dois domínios sensores de Ca2+ adjacentes, denominados CBD1 e CBD2. Apesar da importância fisiológica do NCX, o mecanismo de regulação alostérica do trocador por Ca2+ intracelular permanece desconhecido. Neste trabalho, a espectroscopia de ressonância magnética nuclear (RMN) de alta resolução foi utilizada para investigar a conformação e a dinâmica de CBD1 e CBD2 do trocador de Na+/Ca2+ de Drosophila melanogaster (CALX), isolados ou conectados covalentemente em uma construção denominada CBD12. Um total de 98% das ressonâncias da cadeia principal de CBD1 isolado na presença de Ca2+ foi assinalado, enquanto que na ausência de Ca2+, assinalamentos para apenas uma parte da cadeia principal puderam ser obtidos. Os assinalamentos adquiridos para CBD12 foram baseados na análise de um conjunto de espectros de RMN tridimensional heteronuclear e por comparação com os espectros dos domínios isolados. Uma análise preliminar dos deslocamentos químicos e dos parâmetros de relaxação de 15N obtidos para CBD1 indicou que este domínio é flexível na ausência de Ca2+, mas torna-se rígido após a adição deste íon. As medidas das velocidades de relaxação de 15N e de acoplamentos dipolares residuais (RDCs) de 1H-15N realizadas para CBD12 nas formas apo e holo indicaram que a ligação de Ca2+ em CBD1 estabiliza uma orientação rígida entre os domínios. A análise dos RDCs de 1H-15N mostrou ainda que a orientação média entre CBD1 e CBD2 é praticamente linear na ausência de Ca2+, enquanto que um ângulo menor é assumido após a adição deste íon. Os dados descritos nesta tese suportam um modelo de regulação alostérica em que a modulação da plasticidade de CBD12 pela ligação de Ca2+ no domínio CBD1 controla a abertura e o fechamento do trocador.
The Na+/Ca2+ exchanger (NCX) is a major mechanism for the extrusion of intracellular Ca2+ in excitable cells. It was demonstrated that altered functioning of this protein is related to various pathological situations. Therefore, the understanding of the molecular mechanism for maintaining the intracellular Ca2+ concentration by means of the NCX is important to understand the functioning of the exchanger and to develop drug-based therapies. Besides transporting Na+/Ca2+, the exchanger is also regulated by these ions. The NCX is composed of two transmembrane domains, each of them containing 5 transmembrane alpha-helices (TM), and a very large cytosolic loop that connects TM5 to TM6. The transmembrane domains are responsible for catalyzing the transport of Na+ and Ca2+ ions across the lipid bilayer, while the cytosolic loop is involved in regulation of the exchanger activity. It contains two regulatory Ca2+- binding domains, called CBD1 and CBD2, that appear in tandem. Despite the physiological importance of the NCX, the mechanism of allosteric regulation of the exchanger by intracellular calcium remains unclear. In this work we used high-resolution NMR spectroscopy to study the conformation and the dynamics of the two Ca2+-binding regulatory domains of Drosophila\'s Na+/Ca2+ exchanger (CALX), CBD1 and CBD2, in isolation as well as in a covalent construct called CBD12. Complete backbone NMR resonance assignments were obtained for the isolated CBD1 domain in the Ca2+-bound state, while partial assignments were obtained for CBD1 in the free state. Partial backbone NMR resonance assignments were obtained for the CBD12 construct through the analysis of a standard set of triple resonance NMR spectra. Additional assignments were obtained by comparison with the isolated CBD1 and CBD2 domains. A preliminary analysis of NMR chemical shifts and 15N relaxation data obtained for CBD1 indicates that this domain displays considerable amount of flexibility in the free state, but becomes more rigid upon Ca2+-binding. NMR 15N relaxation rates and 1H-15N residual dipolar couplings (RDCs) obtained for the Apo and Ca2+-bound states of the CBD12 domain indicate that calcium binding stabilizes a rigid inter-domain orientation. Analysis of 1H-15N RDCs further shows that Drosophila\'s CBD12 domain assumes an almost linear inter-domain orientation in the absence of Ca2+, while a smaller inter-domain angle was found in its presence. These findings support a model in which modulation of CBD12 plasticity by the binding of Ca2+ to the CBD1 domain controls the opening and closing of the exchanger.

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Park, Seok-min. "Advanced data exchange for solid freeform fabrication /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004352.

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Johnson, Chad A. "The integration of CAD/CAM with virtual machining simulation and cost estimation." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1177434959.

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Böhme, Carsten, and Klaus Brökel. "Konzept zum Parameteraustausch zwischen unterschiedlichen CAD/CAE-Plattformen." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-228848.

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Einleitung und Motivation Im ZIM-Projekt Vestainnen wird die Entwicklung einer stationären Wirbelschichtfeuerungsanlage (SWSF) kleiner Leistung fortgesetzt. Dabei liegen die Schwerpunkte auf der Modellierung und Simulation der Belastungen an Anlage und den Abläufen in der Feuerung. Insgesamt sind am Projekt sieben Partner beteiligt, die parallel und weitgehend unabhängig arbeiten und die Entwicklung ihres Teilprojekts vorantreiben. Bedingt durch die Vielfalt der Aufgaben kommt bei jedem Partner eine eigene, für die Teilaufgabe geeignete Softwarelösung zum Einsatz. Um die Entwicklungsergebnisse jedoch gemeinsam nutzen zu können, müssen diese eigenständigen Teilmodelle jederzeit auf einen gemeinsamen Stand gebracht werden können, um dieselbe Baugröße und Konfiguration der SWSF abzubilden.

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Böhme, Carsten, and Klaus Brökel. "Konzept zum Parameteraustausch zwischen unterschiedlichen CAD/CAE-Plattformen." TUDpress - Verlag der Wissenschaften GmbH, 2012. https://tud.qucosa.de/id/qucosa%3A30535.

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Einleitung und Motivation Im ZIM-Projekt Vestainnen wird die Entwicklung einer stationären Wirbelschichtfeuerungsanlage (SWSF) kleiner Leistung fortgesetzt. Dabei liegen die Schwerpunkte auf der Modellierung und Simulation der Belastungen an Anlage und den Abläufen in der Feuerung. Insgesamt sind am Projekt sieben Partner beteiligt, die parallel und weitgehend unabhängig arbeiten und die Entwicklung ihres Teilprojekts vorantreiben. Bedingt durch die Vielfalt der Aufgaben kommt bei jedem Partner eine eigene, für die Teilaufgabe geeignete Softwarelösung zum Einsatz. Um die Entwicklungsergebnisse jedoch gemeinsam nutzen zu können, müssen diese eigenständigen Teilmodelle jederzeit auf einen gemeinsamen Stand gebracht werden können, um dieselbe Baugröße und Konfiguration der SWSF abzubilden.

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Sharma, Vishal. "Functional Characterization of Na+/Ca2+ Exchangers in Caenorhabditis elegans." Thesis, The George Washington University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10262140.

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Na⁺/Ca²⁺ exchangers are low affinity/high capacity transporters that mediate Ca²⁺ extrusion by coupling Ca²⁺ efflux to the influx of Na⁺ ions. Their primary function is to maintain Ca²⁺ homeostasis in cells of all organisms and they play a particularly important role in excitable cells that experience transient Ca²⁺ fluxes. While their functions have been studied extensively in muscle cells, much is still unknown about their contributions to the nervous system. Data suggests that Na⁺/Ca²⁺ exchangers play a key role in neuronal processes such as memory formation, learning, oligodendrocyte differentiation and axon guidance. They are also implicated in pathologies such as Alzheimer’s Disease, Parkinson’s Disease, Multiple Sclerosis and Epilepsy. While they are implicated in critical neuronal processes, a clear understanding of their mechanism remains unknown. This dissertation examines the role of Na⁺/Ca²⁺ exchangers in the invertebrate model organism Caenorhabditis elegans . There are ten identified Na⁺/Ca²⁺ exchanger genes in C. elegans (labeled ncx-1 to ncx-10). Data presented here is the first comprehensive description of their genetics and function in C. elegans. The expression pattern of all 10 Na⁺/Ca²⁺ exchanger genes is described and their phylogeny is examined comparatively across humans and flies. Analysis of ncx-2 and ncx-8 mutants shows important roles for Na⁺/Ca²⁺ exchanger genes in egg-laying, lipid storage and longevity, suggesting a role in diverse biological functions for Na⁺/Ca²⁺ exchangers in C. elegans. The function of an NCLX type Na⁺/Ca²⁺ exchanger NCX-9 is also detailed comprehensively. Analysis of ncx-9 mutants shows that NCX-9 is required for asymmetrical axon guidance choices made by the DD and VD GABAergic motor neuron circuit. Pathway analysis shows that NCX-9 regulates asymmetric circuit patterning through RAC-dependent UNC-6/Netrin signaling and LON-2/Glypican Heparan Sulfate signaling. In vitro analysis of NCX-9 physiology in HEK cells shows that NCX-9 is a mitochondrial Na⁺/Ca²⁺ exchanger, similar to NCLX, which is its homolog in humans.

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Jain, Vikesh. "A platform independent process data exchange mechanism between Java applications and computer aided manufacturing systems." Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1081784819.

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Charuk, Jeffrey H. M. "Studies on the development of sarcoplasmic reticulum Ca2+ transport ad sarcolemma Ca2+ exchange systems in embryonic skeletal muscle cultures." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72823.

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Hayashi, Hideharu. "Pathogenesis and the role of Ca2+ overload during myocardial ischemia/reperfusion." Nagoya University School of Medicine, 2000. http://hdl.handle.net/2237/5357.

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Costantini, Mauro, Cuaresma Jesus Crespo, and Jaroslava Hlouskova. "Can Macroeconomists Get Rich Forecasting Exchange Rates?" WU Vienna University of Economics and Business, 2014. http://epub.wu.ac.at/4181/1/wp176.pdf.

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We provide a systematic comparison of the out-of-sample forecasts based on multivariate macroeconomic models and forecast combinations for the euro against the US dollar, the British pound, the Swiss franc and the Japanese yen. We use profit maximization measures based on directional accuracy and trading strategies in addition to standard loss minimization measures. When comparing predictive accuracy and profit measures, data snooping bias free tests are used. The results indicate that forecast combinations help to improve over benchmark trading strategies for the exchange rate against the US dollar and the British pound, although the excess return per unit of deviation is limited. For the euro against the Swiss franc or the Japanese yen, no evidence of generalized improvement in profit measures over the benchmark is found. (authors' abstract)
Series: Department of Economics Working Paper Series

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21

Wan, Yiding. "Can Taylor rule fundamentals predict exchange rates?" Thesis, University of East Anglia, 2012. https://ueaeprints.uea.ac.uk/42380/.

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Recent research suggests that there are many favourable features of the asset- pricing model of exchange rates incorporating Taylor rules. Against this back- ground, this thesis focuses on the relationship between the exchange rate and Taylor rule fundamentals. The introductory chapter provides a short summary of the most relevant literature, and explains the connections between the main chapters. In chapter 2, we mainly follow Engel and West's (2006) framework of the asset-pricing model of exchange rate incorporating Taylor rules to forecast the yen/dollar exchange rate. The central research question is whether this type of model has any predictive power with respect to the exchange rate. In chapter 3, a more detailed analysis of the properties of Taylor rules is un- dertaken. The main idea derives from one of the assumptions made in chapter 2, concerning the structural stability of the Taylor rules. If there are unknown struc- tural breaks, the estimation of the Taylor rule is likely to be biased. Furthermore, both theoretical and empirical studies suggest that the Taylor rule in advanced economies is asymmetric. If a central bank is minimizing an asymmetric loss function in which negative and positive in ation- and output-gap deviation are, respectively, assigned di�erent weights, then a nonlinear Taylor rule is optimal. Hence we set out to identify any structural breaks in the Taylor rule, and to uncover the extent to which nonlinearity plays a role in Taylor rule modelling. In our empirical study, a threshold model introduced by Caner and Hansen (2004) is used to measure whether the Taylor rules are nonlinear or not, in order to explain the existence of asymmetry of Taylor rules. Chapter 4 compares the performance of the traditional monetary model and the Taylor rule model in terms of out-of-sample forecasting performance. A key study is by Molodtsova and Papell (2009) who derive a simple version of the Taylor rule model and demonstrate that it can outperform a variety of monetary models as well as the naive random walk, on the basis of the state-of-the-art goodness-of-�t statistic developed by Clark and West (2006) (the CW statistic). It is of considerable interest to discover whether Molodtsova and Papell's (2009) results are driven by the superior predictability of the Taylor rule fundamentals, or by features of the CW statistic. To address this question, the sterling/dollar exchange rate for the period 1975-2010 is investigated. A detailed analysis of the CW statistic, including Monte-Carlo simulations, is conducted. In addition, a variety of estimators are used, including the Vector Error Correction Method (VECM) which is used to generate the out-of-sample forecast. Also, a number of goodness-of-�t measures (in addition to CW) are used for comparing the pre- dictability of the Taylor rule model with traditional monetary models. The overall �nding is that the out-of-sample forecasting predictability of the sterling/dollar exchange rate obtained by the Taylor rule model is not as signi�cant as we ex- pect by using a variety of goodness-of-�t measures, but the traditional monetary models have certain predictive power if VECM is applied.

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Chacon, Aguilar Ana Gloria. "Oil prices and the CAD / USD exchange rate." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30231/30231.pdf.

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Ce mémoire étudie la relation entre les prix du pétrole et de l’énergie et le taux de change CAD/USD au moyen d’un modèle à correction d’erreur étroitement lié à l’équation du taux de change de la Banque du Canada. Une rupture structurelle se produit dans la relation entre les prix du pétrole et de l’énergie et le taux de change CAD/USD lorsque ce dernier est à parité. Par conséquent, un modèle à correction d’erreur est utilisé pour estimer le taux de change CAD/USD en intégrant l’effet de la parité par rapport à la non-parité dans l’équation de prévision. En outre, la sensibilité de l’équation du taux de change varie selon la présence ou l’absence de parité. Plus précisément, lorsque la parité est atteinte, le taux de change CAD/USD a moins tendance à répondre aux changements de prix du pétrole et de l’énergie.
This thesis studies the relationship between oil and energy prices with the CAD/USD exchange rate using an error correction model closely linked with the Bank of Canada’s exchange rate equation. A structural break occurs in the relationship between oil and energy prices and the CAD/USD exchange rate when this latter is at parity. Accordingly, an error correction model is employed to estimate the CAD/USD exchange rate by incorporating the effect of parity versus non-parity in the forecasting equation. Moreover, the sensitivity of the exchange rate equation shifts in the presence of parity versus the absence of parity. More precisely, when parity occurs, the CAD/USD exchange rate responds less to changes in oil and energy prices.

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Evans, Robert J. "What happens next? : can economic forecasters foretell the future?" Thesis, University of Bath, 1997. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338378.

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Qian, Jingjing. "A Step Implementation For Product Structure Data Exchange." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76684.

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Scania is a Swedish automotive manufacturer for heavy vehicles and engines. It also offers transport solutions and long term commitment for customers. In today's Scania, a modular system provides a huge variety of specifications to meet varying dramatic needs for different customers. In order to be able to meet the diverse requirements of customers, modular approach with the support of reusable components is used to increase the efficiency of designing different products. To customize both product development and product design, computer aided design(CAD) is used to support the process of design and design documentation. "CATIA" is a multi-platform CAD software and "ENOVIA" is a product modeling product offers product database management for virtual model design into CATIA, both "CATIA" and "ENOVIA" are developed by the French company Dassault Systemes are chosen by Scania to support its product development. The modular system approach requires the system support for product structure, which is managed by a mainframe called SPECTRA. The thesis project is mainly about system designing a new module which takes the responsibility for exchanging information between SPECTRA and ENOVIA. In more detail, the new component is to perform a mapping of data in SPECTRA format into a format which ENOVIA can import. The mapping module has several interfaces with other applications in the system. JavaMigrator provides the environment to import data from the mainframe and transfer the data into the module and finally output the expected data format into ENOVIA. To achieve this purpose, several possible solutions were proposed and several methods were tried. Since an in-house developed CAA-module is highly preferred by Scania, the new mapping component will finally be designed into two separate modules, the first part converts the XML extracted from SPECTRA into an intermediate format and the second part is designed to convert the intermediate file into the expected target file. The intermediate file is required, since the format is independent of changes in both SPECTRA and ENOVIA. Furthermore, it is flexible and less complex to maintain than direct mapping from exported XML to ENOVIA. The report focuses on five parts, background, project specification, methodology, implementation, result and future work.

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Nebaneh, Nixon, and Shella Ndobe. "An Analysis of Exchange Rate Variability and Stock Returns : A Swedish Perspective." Thesis, Umeå universitet, Handelshögskolan vid Umeå universitet, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-38390.

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The emergence of capital markets in Asia and South America, the relaxation of foreign capital controls and the adoption of flexible exchange rate regimes has prompted heavy cross-border investments in recent years. Simultaneously, volatility in these foreign exchange markets has increased, leading to increased risk following the adoption of these flexible exchange regimes. As such, investors have become more interested in knowing what impact the volatile markets have on their investments. This, they seek to know, through the returns on their stock investments as stock prices are said to be a representation of firm value. This thesis uses firm size as a parameter to analyse the role of macroeconomic variables with emphasis on exchange rate variability on stock returns using data from 67 Swedish companies listed on the Stockholm stock exchange and selected from all the three market capitalization segments (large cap, mid cap and small cap) according to the OMX index classification. We used returns from all the non-financial firms listed on the Stockholm stock exchange between the years 1997 to 2009. Based on the Arbitrage Pricing Theory, and using multiple regression model, we sought to ascertain if the effect of movements in the SEK/USD and SEK/Euro exchange rates are different for companies of the small, mid and large capitalizations segments of the OMX Stockholm stock exchange and which other control variables will influence these returns more than the exchange rate movements. Using bilateral monthly exchange rates for the USD and Euro, we find that 55 out of the 67 companies are significantly exposed to exchange rate changes within all the segments. These are almost evenly distributed relatively across all the capitalization segments though the absolute numbers may differ considerably. We further use one-way ANOVA to find out if there are any differences in the means of the exposures of the companies in the respective segments. Still, we find no significant difference in their means. These therefore give little evidence to conclude that there is actually a difference in the exposure of firms in the respective capitalisation segments to exchange variations. We also discover that apart from exchange rate variations, other macroeconomic variables also play a big role in determining the returns of the stocks of firms.

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Thell, Mats. "Utvärdering av kalenderöverföringsstandarden CAP." Thesis, University of Skövde, Department of Computer Science, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-787.

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Vi lever i ett stressigt samhälle där allt skall fungera och tiden är emot oss för det mesta. Ifall det gick att schemalägga alla händelser som skall och borde göras i ett gemensamt kalendersystem så skulle det förenkla situationen för många personer, som skall träffas eller andra händelser som kan uppstå. I detta arbete undersöks det ifall en ny öppen standard för kalenderöverföringar skulle fungera, samt om den är tillräckligt bra för att användas, eller om den skall undvikas. Inom arbetet implementeras en prototyp som baseras på denna kalenderöverföringsstandard. Den prototyp som framtogs, tillhandahåller de grundläggande funktionerna i CAP, jämförs med Microsoft Exchange. Slutsatserna av arbetet är att CAP är bra, enkelt och smidigt men protokollet är dock ej klart för att användas som en färdigutvecklad produkt.

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Antonakakis, Nikolaos, and Julia Darby. "Forecasting volatility in developing countries' nominal exchange returns." Routledge, 2013. http://dx.doi.org/10.1080/09603107.2013.844323.

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This article identifies the best models for forecasting the volatility of daily exchange returns of developing countries. An emerging consensus in the recent literature focusing on industrialized countries has noted the superior performance of the Fractionally Integrated Generalized Autoregressive Conditionally Heteroscedastic (FIGARCH) model in the case of industrialized countries, a result that is reaffirmed here. However, we show that when dealing with developing countries' data the IGARCH model results in substantial gains in terms of the in-sample results and out-of-sample forecasting performance. (authors' abstract)

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Atturo, Giulia <1992&gt. "The yuan exchange rate and firms - How the Chinese exchange rate can influence strategic entering into the Chinese market." Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/11639.

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When we talk about China now, we talk about the second major economy in the world but what is more important is that China had reached this goal in less than 40 years. Chinese’s growth data are impressing: from 1978 to 1985 China tripled its income per capita. Above all, in the past China was a closed and isolated country that started to expand its international relationships, thanks to the gradual opening to foreign investments. But, even though China made progress in leaps and bounds, it’s not a Market Economy yet, and its economy can, in different ways, still affect some other great economies, such as the USA, and competitors in the world. Nevertheless, China has gained the righ to become one of the member of the WTO, and this means that its economic conditions are now something that all government have to care about. The most important issue of this thesis is without a doubt Chinese monetary policy and the value of the Chinese yuan (元), or renminbi as Chinese use to call it. As we will explain later, the value of a currency can influence the productivity, investments and trade of a country, and, as a consequence, can have influence also on a country long-term growth rate. It will be also clear how a fixed exchange rate can be more affecting than a flexible one, because a fixed exchange rate can reduce the uncertainty, even if it has more risks in terms of economic stabilization. On commercial deficit/surplus between countries literature has been arguing for a long time: at first the problem seemed to be the fixed exchange rate system under the Bretton Woods agreement, and the only solution was thought to be a flexible exchange rate system, but now the problem is maybe more extended that in the Bretton Woods period. So maybe the flexible exchange rate is not a solution to commercial imbalance. What it’s more surprising is that the Chinese yuan exchange is so low, while the country growth rate is still so high. What we want to understand is why Chinese government does not allow its currency to freely move? And why a currency devalues/revalues? Since that international economies are tied each other by commerce and capital flows, this means that a country’s economic conditions influence the currency value, in a sort of vicious circle. But there’s more: monetary policy (of course), tax of interests, the inflation rate and the public debt influence the currency values. We will explain how and how strong is the influence of this factor on Chinese RMB value. What can be more interesting is what can happen if China revalues and what if devalues. Each situation can have different consequences. The Chinese market it’s now so important for the entire economy that all countries are, in a certain way, involved in this matter, and that each of the two possibility has some bad consequences, especially for export and import in China. This analysis can be useful to give an important reflection point for European companies that want to locate their production in China. Understanding how the Chinese value can impact cross border trade is a matter of particular interests, especially for policymakers and investors. From the studied we had analyzed a money revaluation increases the possibility of an export market exit, reduce the possibility of export market survival and decrease the chance of export market entry. During a period of exchange rate appreciation, high productivity firms, are more likely to enter and survive in export market. For private-owned company, young and non-eastern firms, an exchange rate appreciation decreases the likelihood of export market entering and increase the exit. Exchange rate affects at the same time also import, both prices and import volume. How? And How an exchange rate can influence the strategic entering of a firm into the Chinese market? This is what we are trying to understand and explain.

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Popova, Maria. "Characterization of the interaction between NA⁺/H⁺ exchanger isoform 7 (NHE7) and calmodulin (CaM)." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/24209.

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Na⁺/H⁺ exchangers (NHEs) are a family of transmembrane antiporters that catalyze the electroneutral exchange of Na⁺ and H⁺. They are primarily involved in regulation of pH and ion homeostasis and are themselves regulated by several signaling pathways, including Ca²⁺ signaling. NHE isoform 7 (NHE7) is activated by increases in intracellular Ca²⁺ , mediated by binding of calmodulin (CaM) to the second intracellular loop (1L2) of NHE7. This interaction between NHE7 1L2 and CaM is unconventional, as NHE7 1L2 is an extremely short CaM-binding site (∼10 amino acids) unlike previously characterized CaM-binding sites. We showed that the NHE7 1L2-CaM interaction is likely pH-independent by means of pulidown assays with GST fusion peptides of NHE7 1L2 and immobilized CaM beads performed under pH 7.3 and pH 5.8. We also showed that the NHE7 1L2-CaM interaction is mediated by positively charged and hydrophobic amino acids by means of pulidown assays with GST fusion peptides of mutant NHE7 1L2 (NHE7 1L2 KKPL, NHE7 1L2 KKRAAA and NHE7 1L2 FFAA) and immobilized CaM beads. The interaction between NHE7 1L2 and CaM has potential for relevance to the nervous system, which is highlighted by the numerous NHE isoforms that have been implicated in neuronal function: NHE1, NHE6 and NHE9. However, much future research needs to be done to elucidate the exact nature of the contribution to physiology and the nervous system of the NHE7-CaM interaction.

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30

Höijer, Mattias, Martin Lejdelin, and Patrik Lindén. "Price Drift on the Stockholm Stock Exchange." Thesis, Jönköping University, Jönköping International Business School, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-635.

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This paper examines whether the phenomena of price drift around quarterly earnings re-leases exist among firms listed on the large cap. list at the Stockholm Stock Exchange for a time period ranging from the first quarter of 2003 to the second quarter of 2006. It fur-thermore examines the ability of the variables forecast error, relative to analyst’s estimates, and firms’ size to explain the variation in price drift among firms.

A sample of some 30 firms were drawn in the first three quarters of each year between 2003 and 2005, for the year of 2006 only the fist two quarters were included in the study. For each quarter all firms were classified into three different portfolios on the basis of earnings deviations relative to mean analyst’s estimates (forecast error). The returns for each firm in all portfolios were investigated during 20 days post- and pre quarterly earnings release date, resulting in an event window totaling 41 days. In order to clear out effects from general market movements the Capital Asset Pricing Model, CAPM, was used in which betas were estimated for all firms each quarter.

The findings from this study indicate that price drift, measured by cumulative abnormal re-turn, occur for firms with both negative forecast error as well as positive. For firms with positive error, statistically significant positive price drift was found for both the pre- and post period. As for the firms with earnings below analyst’s mean estimates, negative prean-nouncement drift was statistically supported.

The ability of firms size and forecast error to explain the variation in price drift on a stock level was very weak, R2 measures of below 5% was reported. However, forecast error was a strongly significant independent variable in the context of the regressions run for both pre- and post-announcement drift. The firms below the lower market cap. quartile in the sample show, on average, lower pre-announcement drift than the firms belonging in the largest quartile.

Concerning market efficiency among the large cap. firms the price drift found is an indica-tion of market inefficiency both it terms of the semi strong and the strong form. However, care should be taken before generalizing the results from this study but. Possible misspeci-fication of the equilibrium return model will skew the price drift measurement. Moreover, speculation is not explicitly controlled for in this test. Finally, this study is done within a li-mited time span; hence generalization over time is not possible

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31

Lee, Ryan S. "Effect of the Ca2+ Binding Properties of Troponin C On Skeletal and Cardiac Muscle Force Development." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274968255.

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32

Rajab, Khairan. "Knowledge Guided Non-Uniform Rational B-Spline (NURBS) for Supporting Design Intent in Computer Aided Design (CAD) Modeling." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3302.

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For many years, incompatible computer-aided design (CAD) packages that are based on Non-uniform Rational B-Spline (NURBS) technology carried out the exchange of models and data through either neutral file formats (IGES or STEP) or proprietary formats that have been accepted as quasi industry standards. Although it is the only available solution at the current time, the exchange process most often produces unsatisfactory results. Models that are impeccable in the original modeling system usually end up with gaps or intersections between surfaces on another incompatible system. Issues such as loss of information, change of data accuracy, inconsistent tolerance, and misinterpretation of the original design intent are a few examples of problems associated with migrating models between different CAD systems. While these issues and drawbacks are well known and cost the industry billions of dollars every year, a solution to eradicate problems from their sources has not been developed. Meanwhile, researchers along with the industries concerned with these issues have been trying to resolve such problems by finding means to repair the migrated models either manually or by using specialized software. Designing in recent years is becoming more knowledge intensive and it is essential for NURBS to take its share of the ever increasing use of knowledge. NURBS are very powerful modeling tools and have become the de facto standard in modeling. If we stretch their strength and make them knowledge driven, benefits beyond current expectations can be achieved easily. This dissertation introduces knowledge guided NURBS with theoretical and practical foundations for supporting design intent capturing, retrieval, and exchange among dissimilar CAD systems. It shows that if NURBS entities are tagged with some knowledge, we can achieve seamless data exchange, increase robustness, and have more reliable computations, all of which are ultimate objectives many researchers in the field of CAD have been trying to accomplish for decades. Establishing relationships between a NURBS entity and its origin and destinations can aid with seamless CAD model migration. The type of the NURBS entity and the awareness of any irregularities can lead to more intelligent decisions on how to proceed with many computations to increase robustness and achieve a high level of reliability. As a result, instead of having models that are hardly modifiable because of migrating raw numerical data in isolation, the knowledge driven migration process will produce models that are editable and preserve design intent. We have addressed the issues not only theoretically but also by developing a prototype system that can serve as a test bed. The developed system shows that a click of a button can regenerate a migrated model instead of repairing it, avoiding delay and corrective processes that only limit the effective use of such models.

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33

Otto, E., S. Rubbert, and J. Borrmeister. "Thermodynamics and charge exchange of the new BMW six-cylinder engine." Sage, 2000. https://publish.fid-move.qucosa.de/id/qucosa%3A38437.

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The BMW in-line six-cylinder engine has been modified and introduced to production in the new BMW 3 Series model. Its major features include variable intake and exhaust camshaft timing, a new induction system with resonance charging, a turbulence-generating system in the intake ports and a new exhaust system with two closed-loop, coupled catalysts integrated into the exhaust manifold. The cam timing of both camshafts can be adjusted continuously within a range of 40° crank angle (CA) for the inlet cams and 25° CA for the exhaust cams. The turbulence-generating system supplies combustion air to the engine during part load operation and produces the necessary charge motion to run the engine with greater valve overlap at low loads and speeds. Its combination with variable camshaft timing results in lower fuel consumption and exhaust emissions that meet the LEV emission standard. In addition, the variable cam timing raises the torque curve of the unthrottled engine, particularly at low engine speed. The maximum values for torque and power output are unchanged, but maximum torque is reached 500 r/min earlier than with the previous engine.

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34

Jain, Vikesh. "A PLATFORM INDEPENDENT PROCESS DATA-EXCHANGE MECHANISM BETWEEN JAVA APPLICATIONS AND CAM SYSTEMS." Ohio University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1081784819.

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35

Oz, Emrah. "Can Relative Yield Curves Predict Exchange Rate Movements? Example From Turkish Financial Market." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612505/index.pdf.

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Exchange rate forecasting is hard issue for most of floating exchange rate economies. Studying exchange rate is very attractive matter since almost no model could beat random walk in short run yet. Relative yields and information in relative yield curves are contemporary topics in empirical literature and this study follows Chen and Tsang (2009) who model exchange rate changes with relative factors obtained from Nelson-Siegel (1987) yield curve model and find that relative factor model can forecast exchange rate change up to 2 years and perform better than random walk in short run. Analysis follows the methodology defined by Chen and Tsang (2009) and TL/USD, TL/EUR exchange rate changes are modeled by the relative factors namely relative level, relative slope and relative curvature. Basically, 162 weekly datasets from 09.01.2007 to 16.03.2010 are used and the relative factors for each week are estimated. Afterwards, regression analysis is made and results show that relative level and relative curvature factors are significant up to 4-6 weeks horizon but relative slope does not provide any valuable information for exchange rate prediction in Turkish financial market. Length of forecasting horizon of relative factor model is too short when compared to other exchange rate models. Since it is accepted that exchange rates follow random walk, we provided some tests to compare performance of the model. Similar to the literature, only short run performance of relative factor model is compared to random walk model and concluded that the relative factor model does not provide better forecasting performance in Turkish financial market

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36

Tarandi, Väino. "Neutral intelligent CAD communication : information exchange in construction based upon a minimal schema." Doctoral thesis, KTH, Fastigheter och byggande, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2657.

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An improved information exchange is frequently proposed asone solution to the inefficiency problems which theconstruction industry is suffering from today. Such animprovement is very dependent of the use of informationtechnology, IT. To enable an advanced use of IT, there is aneed for integrated project communications frameworks andintegrated industry wide information. This thesis discusses how product models can be used toimprove the information exchange from design to construction.Today there are several approaches to product modelling. Someresearchers propose very detailed models whereas others proposegeneric models with fewer concepts. In this area there is aclose connection between research and standardisation, which iscarried out by organisations such as the ISO STEP committee andthe International Alliance for Interoperability. To get acceptance for a standard proposal, it has to beaccepted by both users and standardisation bodies. Thus thisresearch, in addition to the technical requirements oninformation content and structure, also discusses successfactors for standardisation, implementation and usage. In order to define important requirements on a product modelfor information exchange between design and construction,current research, development and standardisation in the fieldof product modelling was studied. This thesis advocates a minimal approach in the number ofconcepts used in a product model, in combination with anexternal building element classification, following nationalindustry practice. The minimal NICC schema, developed duringthis research, was tested in a prototype and test study. Threeapplications were tested: PreFacto (planning tool), MicrosoftProject (time scheduling tool) and Calc3(cost estimation tool).From the CAD-system MCAD, NICC files with the building objectswere created and transferred into a relational database fromwhich the three applications received their specific inputfiles. The results of the evaluation of the NICC schema and thetest study demonstrated that a product model based on fewconcepts can manage the required information exchange. Keywords:construction, product models, standardisation,minimal models, requirements, conceptual schema, thesis
QC 20120124

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Tarandi, Väino. "Neutral intelligent CAD communication : information exchange in construction based upon a minimal schema /." Stockholm : Tekniska högsk, 1998. http://www.lib.kth.se/abs98/tara0529.html.

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Trapletti, Adrian, Alois Geyer, and Friedrich Leisch. "Cointegration and exchange market efficiency. An analysis of high frequency data." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 1999. http://epub.wu.ac.at/1346/1/document.pdf.

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A cointegration analysis on a triangle of high frequency exchange rates is presented. Market efficiency requires the triangle to be cointegrated and the cointegration term to be a martingale difference sequence. We find empirical evidence against market efficiency for very short time horizons: The cointegration term does not behave like a martingale difference sequence. In an out-of-sample forecasting study the cointegrated vector autoregressive (VAR) model is found to be superior to the naive martingale. Finally, a simple trading strategy shows that the VAR also has a significant forecast value in economic terms even after accounting for transaction costs. (author's abstract)
Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

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39

Lehner, Zachary M. "Determinants of exchange rate hedging an empirical analysis of U.S. small-cap industrial firms." Honors in the Major Thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/459.

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Using a sample of 141 U.S. small-cap industrial firms, I examine the firm characteristics that influence its use of foreign exchange derivatives to hedge exchange rate risk. Companies in the industrial sector produce goods and services that are used for the production of another final product. The performance of this sector is closely correlated to the level of demand from the final consumer. I find firm size, the amount of foreign sales, and firm liquidity influence the firm's decision to use foreign exchange derivatives to hedge exchange rate risk. For those firms that hedge exchange rate risk using derivatives, a second test examines the firm characteristics that influence the extent of its hedging activities. I find the extent of hedging is influenced by the amount of foreign sales, the amount of foreign assets, and the number of foreign subsidiaries the firm operates. A final test examines whether certain firm characteristics influence its decision to use options as part of its hedging operations. I find no evidence that the firm characteristics examined herein influence that decision.
B.S.B.A.
Bachelors
Business Administration
Finance

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40

Fallman, David, and Jens Wirf. "FORECASTING FOREIGN EXCHANGE VOLATILITY FOR VALUE AT RISK : CAN REALIZED VOLATILITY OUTPERFORM GARCH PREDICTIONS?" Thesis, Uppsala universitet, Statistiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-146571.

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In this paper we use model-free estimates of daily exchange rate volatilities employing high-frequency intraday data, known as Realized Volatility, which is then forecasted with ARMA-models and used to produce one-day-ahead Value-at-Risk predictions. The forecasting accuracy of the method is contrasted against the more widely used ARCH-models based on daily squared returns. Our results indicate that the ARCH-models tend to underestimate the Value-at-Risk in foreign exchange markets compared to models using Realized Volatility

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López-Ballesteros, Ana, Cecilio Oyonarte, Andrew S. Kowalski, Penélope Serrano-Ortiz, Enrique P. Sánchez-Cañete, M. Rosario Moya, and Francisco Domingo. "Can land degradation drive differences in the C exchange of two similar semiarid ecosystems?" COPERNICUS GESELLSCHAFT MBH, 2018. http://hdl.handle.net/10150/626541.

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Currently, drylands occupy more than one-third of the global terrestrial surface and are recognized as areas vulnerable to land degradation. The concept of land degradation stems from the loss of an ecosystem's biological productivity due to long-term loss of natural vegetation or depletion of soil nutrients. Drylands' key role in the global carbon (C) balance has been recently demonstrated, but the effects of land degradation on C sequestration by these ecosystems still need to be investigated. In the present study, we compared net C and water vapor fluxes, together with satellite, meteorological and vadose zone (CO2, water content and temperature) measurements, between two nearby (similar to 23 km) experimental sites representing "natural" (i.e., site of reference) and "degraded" grazed semiarid grasslands. We utilized data acquired over 6 years from two eddy covariance stations located in southeastern Spain with highly variable precipitation magnitude and distribution. Results show a striking difference in the annual C balances with an average net CO2 exchange of 196 +/- 40 (C release) and 23 +/- 2 gCm(-2) yr(-1) (C fixation) for the degraded and natural sites, respectively. At the seasonal scale, differing patterns in net CO2 fluxes were detected over both growing and dry seasons. As expected, during the growing seasons, greater net C uptake over longer periods was observed at the natural site. However, a much greater net C release, probably derived from subterranean ventilation, was measured at the degraded site during drought periods. After subtracting the nonbiological CO2 flux from net CO2 exchange, flux partitioning results point out that, during the 6 years of study, gross primary production, ecosystem respiration and water use efficiency were, on average, 9, 2 and 10 times higher, respectively, at the natural site versus the degraded site. We also tested differences in all monitored meteorological and soil variables and CO2 at 1.50m belowground was the variable showing the greatest intersite difference, with similar to 1000 ppm higher at the degraded site. Thus, we believe that subterranean ventilation of this vadose zone CO2, previously observed at both sites, partly drives the differences in C dynamics between them, especially during the dry season. It may be due to enhanced subsoil-atmosphere interconnectivity at the degraded site.

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42

Chweih, Hanan 1990. "Especificidades teciduais e de sexo no transporte de Ca2+ por mitocôndrias isoladas = avaliações em condições que impedem a transição de permeabilidade = Tissue and sex especifities in the Ca2+ handling by isolated mitochondria: evaluations under conditions avoiding the permeability transition." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313112.

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Orientadores: Tiago Rezende Figueira, Roger Frigério Castilho
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Algumas das características das mitocôndrias, incluindo as suas funções de transporte de Ca2+, podem apresentar dimorfismo sexual e especificidades teciduais. No entanto, as mensurações do transporte de Ca2+ em mitocôndrias isoladas estão sujeitas a artefatos secundários a abertura do poro de transição de permeabilidade mitocondrial (PTP) induzido pelo acúmulo excessivo de Ca2+ nesta organela. Neste estudo, o objetivo inicial foi avaliar se a inibição do PTP pela ciclosporina A (CsA) afeta a mensuração de diversas variáveis que descrevem o transporte de Ca2+por mitocôndrias isoladas de fígado de rato. Os resultados obtidos indicam que as concentrações de estado estável do Ca2+ externo a mitocôndria e as taxas deefluxo mitocondrial de Ca2+através de trocadores seletivos foram superestimados em até 4 vezes quando o PTP não foi inibido farmacologicamente pela CsA. O objetivo subsequente foi analisar o transporte de Ca2+ em mitocôndrias isoladas de fígado, de músculo esquelético, de coração e de cérebro de ratos machos e fêmeas sob condições experimentais específicas (i.e. meio de incubação contendo inibidores TPM, substratos energéticos ligados a NAD e níveis relevantes de Ca2+, Mg2+e Na+). Os dados indicaram que a taxa de influxo de Ca2+em mitocôndrias de fígado foi ~4 vezes superior a dos outros tecidos, as quais foram semelhantes entre si. Em contrapartida, as taxas de efluxo de Ca2+ apresentaram uma maior diversidade entre tecidos, especialmente na presença de Na+. Curiosamente, o efluxo de Ca2+na ausência de Na+foi significativamente mais elevado nas mitocôndrias cardíacas (~4nmol/mg/min) em relação às taxas observadas nos outros tecidos, contrariando a concepção de que o efluxo de Ca2+de mitocôndrias de coração é dependente, quase que exclusivamente, de um trocador que requer Na+. A especificidade em relação ao sexo só foi observada em dois índices relacionados a homeostase mitocondrial de Ca2+(i.e. cinética geral normalizada da captação de Ca2+ e a concentração de estado estável do Ca2+ externo a mitocôndria) em mitocôndrias isoladas de coração (mais lentos ou maiores na fêmea) e na respiração estimulada por ADP em mitocôndrias de fígado (~20% maior na fêmea). O presente estudo demonstrou a importância metodológica de se prevenir a abertura do PTP para a análise das propriedades e da variabilidade fisiológica do transporte de Ca2+por mitocôndrias isoladas. Adicionalmente, concluímos que sob as condições experimentais aqui utilizadas, o efluxo de Ca2+ mitocondrial apresenta grandes especificidades teciduais e que alguns achados desafiam conceitos estabelecidos em estudos anteriores sob condições arguivelmente menos controladas
Abstract: The characteristics of mitochondria, including their Ca2+ transport functions, may exhibit tissue specificity and sex dimorphism. Because the measurements of the Ca2+ handling by isolated mitochondria may be biased by dysfunction secondary to Ca2+-induced mitochondrial permeability transition (MPT) pore opening, this study evaluates the extent to which MPT inhibition by cyclosporine-A affects the measurement of Ca2+ transport in isolated rat liver mitochondria. The results indicate that the steady-state levels of external Ca2+ and the rates of mitochondrial Ca2+ efflux through the selective pathways can be overestimated by up to 4-fold if MPT pore opening is not prevented. Then, we analyzed the Ca2+ transport in isolated mitochondria from the liver, skeletal muscle, heart and brain of male and female rats under incubation conditions containing MPT inhibitors, NAD-linked substrates and relevant levels of free Ca2+, Mg2+ and Na+. Except for the liver mitochondria displaying values4-fold higher, the Ca2+ influx rates were similar among the other tissues. In contrast, the Ca2+ efflux rates exhibited more tissue diversity, especially in the presence of Na+. Interestingly, the Na+-independent Ca2+ efflux was highest in the heart mitochondria (~4 nmol/mg/min), thus challenging the view that heart mitochondrial Ca2+ efflux relies almost exclusively on a Na+-dependent pathway. Sex specificity was only observed in two kinetic indexes (i.e. the normalized overall kinetics of Ca2+ uptake and the steady-state levels of external Ca2+) of heart mitochondrial Ca2+ homeostasis (slower or higher in female)and in the ADP-stimulated respiration of liver mitochondria (~20% higher in females). The present study shows the methodological importance of preventing MPT when measuring the properties and the physiological variability of the Ca2+ handling by isolated mitochondria. Moreover, we conclude that mitochondrial Ca2+ efflux exhibits great tissue specificity under our conditions, which may challenge some concepts raised in previous studies that employed experimental conditions that are arguably not well controlled
Mestrado
Fisiopatologia Médica
Mestra em Ciências

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43

Bottau, Francesco. "Design and optimization af a race car cooling system." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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The aim of this thesis is the design and the optimization of water radiator for the Tatuus F3 race car. Tatuus is a racing car manufacturer which designs, produces and sells cars for different racing categories. In a race car is essential that weight and occupied volume are kept as low as possible. This requirement is achieved by optimizing the vehicle’s components. For this reason, Tatuus commissioned a project focused on the optimization of heat exchangers. It is very important that the flow inside every radiator is as uniform as possible, to make it works in the most efficient way. With this respect, if in some channels the flow-rate is low or nil, they do not contribute to the cooling process, hence represent a waste of space and weight. To avoid this, it is crucial that inlet and outlet collectors have a shape such that the flow is distributed almost uniformly inside each channel. This optimization can be obtained simulating different radiator configuration with CFD software and analyzing the internal flow distribution. Using simulation solutions, it was possible to design radiators that guarantee a sufficiently uniform flow.

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Mahon, Maureen F. "Parents and teachers in education, can social exchange theory explain the nature of the relationship?" Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ32175.pdf.

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45

Hitzing, Christoffer [Verfasser], Jürgen [Akademischer Betreuer] Wienands, and Lutz [Akademischer Betreuer] Walter. "Vav guanine nucleotide exchange factors control B cell antigen receptor-induced Ca2+-signaling / Christoffer Hitzing. Betreuer: Jürgen Wienands. Gutachter: Jürgen Wienands ; Lutz Walter." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://d-nb.info/1093193298/34.

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Lopes, João Henrique 1982. "Biovidros derivados do 45S5 : os efeitos do Nb2O5 ou da modificação da superfície com Ca2+ sobre a estrutura e bioatividade." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250001.

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Orientadores: Celso Aparecido Bertran, Italo Odone Mazali
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Esta tese está dividida em quatro capítulos. O capítulo I apresenta os fundamentos sobre biomateriais e biovidros. O capítulo II é dedicado a investigar os efeitos da adição de óxido de nióbio (Nb2O5) sobre as propriedades físicas, a estrutura do vidro e a bioatividade de duas séries vítreas derivadas do 45S5 Bioglass® (BG45S5). A composição química do BG45S5 foi modificada pela substituição de 1,3 e 2,6% de P2O5 por Nb2O5 e 1, 2 e 5% do SiO2 pelo Nb2O5, gerando as séries (I) e (II), respectivamente (BGNs). A introdução do Nb2O5 aumenta significativamente a densidade e a estabilidade contra a desvitrificação, como evidenciado pelo parâmetro ?Txg = (Tx - Tg). Os espectros de ressonância magnética nuclear no estado sólido MAS NMR para os núcleos 29Si, 31P e 23Na, espectroscopia Raman e a determinação de algumas propriedades físicas permitiu um entendimento detalhado da estrutura dos vidros BGNs. Para os vidros da série I, o octaedro de NbO6 entra na rede silicato, partilhando os seus vértices com os tetraedros de silício para formar cadeias O-Si-O-Nb-O-Si-O, enquanto que para os vidros da série II, os octaedros NbO6 atuam como agente de reticulação para as cadeias de silicatos. A viabilidade celular e a atividade metabólica foram determinadas utilizando o ensaio de MTT. Os resultados dos estudos in vitro com os vidros BGNs sobre a viabilidade dos osteoblastos e proliferação não mostram diferenças significativas entre BGNs e BG45S5. Os resultados da experimentação in vivo em ratos Wistar sugerem que a presença de Nb2O5 pode efetivamente promover um aumento na bioatividade de BGNs, observado pelo aumento da quantidade formada de osso cortical e trabecular. O capítulo III abrange a investigação da modificação da superfície do biovidro BG45S5 pelo enriquecimento com cálcio, por imersão em banho de sal fundido contendo cálcio (BG45Cas) e o seu efeito sobre a estrutura da superfície, a velocidade de dissolução e também a cinética da formação do fosfato de cálcio. A combinação da microscopia de força atômica e espectroscopia Raman (AFM) permitiu o acompanhamento das mudanças estruturais do BG45S5 submetido a diversos tempos de imersão no banho de sal fundido a 480 °C, enquanto que a fluorescência de raios X (XRF) foi empregada para monitorar a evolução temporal do processo de troca iônica entre Ca2+ e Na+. Os rearranjos estruturais, como resultado da troca iônica, foram sistematicamente investigados no BG45Ca30 pelas espectroscopias FTIR e 29Si e 31P MAS NMR. Os resultados mostram que a quantidade de íons cálcio que entram na estrutura do vidro é maior do que a quantidade de íons sódio que deixa a rede, de modo que, para preservar a eletroneutralidade na rede, ocorrem alterações locais na estrutura que conduzem a uma depolimerização da rede de silicato. A formação da fase de fosfato de cálcio quimicamente equivalente à hidroxiapatita (HA) na superfície do biovidro foi estudada por imersão dos biovidros em HEPES 50,69 mmol L-1 e fluido corpóreo simulado (SBF) durante 2 dias. A camada de apatita formada foi caracterizada pela espectroscopia 31P MAS NMR. A cinética de crescimento da camada de apatita sobre a superfície do BG45Ca30 sugere que a modificação da superfície do vidro não só promove uma redução no tempo para a formação de HA, mas também a formação de hidroxiapatita com maior grau de cristalinidade. Finalmente, o capítulo IV descreve as nossas contribuições, observações finais e sugestões para futuros trabalhos
Abstract: This thesis is divided into four chapters. Chapter I presents background information on the biomaterial and bioglasses. Chapter II is devoted to investigate the effects of adding niobium oxide (Nb2O5) on the physical properties, glass structure and bioactivity of two glasses series derived from the 45S5 Bioglass® (BG45S5). The chemical composition of BG45S5 was modified by replacing 1.3 and 2.6% of P2O5 with Nb2O5 and 1, 2.5, and 5% of SiO2 with Nb2O5, generating series (I) and (II), respectively (BGNs). Adding Nb2O5 significantly increases the density and the stability against devitrification as indicated by ?Txg = (Tx - Tg). The multinuclear 29Si, 31P, and 23Na solid-state MAS NMR spectra of the glasses, Raman spectroscopy, and the determination of some physical properties have generated insight into the structure of the glasses. For the series I glasses, the octahedral niobium take part in glasses network, sharing its corners with silicon tetrahedra forming O-Si-O-Nb-O-Si-O chains, whereas for the series II, NbO6 octahedra act as crosslinker for the silicates chains. Cell viability and metabolic activity were determined using the MTT assay. We investigated the in vitro effect of BGNs glasses on osteoblast viability and proliferation. No significant differences were found between BGNs and BG45S5. Furthermore, in vivo tests in Wistar rats have suggested that the presence of Nb2O5 might actually promote an increase in bioactivity of BGNs, increasing formation of cortical and cancellous bones. The chapter III covers research related to of the surface modification of BG45S5 bioglass (BG45Cas) and its effect on the surface structure, dissolution rate and calcium phosphate formation. BG45Cas were obtained by ion exchange method by immersion in molten salt bath containing calcium. The combination of Raman spectroscopy and atomic force microscopy (AFM) allowed the monitoring of the structural changes of BG45S5 bioglass submitted to increasing durations of immersion in the molten salt bath at 480 °C, whereas X-ray Fluorescence (XRF) was employed to derive the time evolution of Ca2+-Na+ ion exchange process. Structural rearrangements as a result of Ca2+-Na+ ion exchange have been investigated systematically on 45S5 bioglasses by FTIR and 29Si and 31P MAS NMR spectroscopies. Results show that the insertion of calcium ions in the glass structure is higher than the departure of sodium ions. The electroneutrality of the glass structure is preserved with local alterations, which lead to a higher degree of depolymerization of the silicate network. The formation of calcium phosphate layer chemically equivalent to hydroxyapatite (HA) on the bioglass surface was evaluated by immersing the bioglasses in the HEPES 50,69 mmol L-1 and simulated body fluid (SBF) for up to 2 days. This apatite layer was characterized by 31P MAS NMR spectroscopy. The growth kinetics of the apatite layer on the surface of the bioglasses demonstrated that modification of the glass surface (BG45Ca30) cause not only a reduction in time of the formation of HA, but also induced hydroxyapatite phase formation with a higher degree of crystallinity. Finally, chapter IV describes our contributions, final remarks and suggests some ideas for future works
Doutorado
Físico-Química
Doutor em Ciências

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47

Sameh, Ebong F. "Sorption of Ni and Eu to granitic rocks and minerals." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9324.

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The work presented in this thesis is divided into two parts. The first part is the sorption of Ni and Eu to granitic materials, and cation exchange capacity measurements for powdered and intact samples. The second part is method development on autoradiography. In the first part, static batch sorption experiments were carried out to study the relative sorption properties of different granitic rocks and minerals. Experimental data were described using non-electrostatic correction models such as the Langmuir, Freundlich and Linear models. Sorption data obtained for sorption in a constant pH environment and variable metal concentration were used to test the Component Additive Model (CAM). Sorption test studies carried out using energy dispersive X-ray microanalysis were used to map the sorption of Eu on an intact sample. The results showed the CAM was applicable for Ni sorption to BG but that it was not applicable for Eu sorption to any of the granitic rocks studied. The sorption data fitted the CAM in the following order; BG (1) > GA (0.7) > RG (0.5) > GG (0.2), GrG (0.2) for Ni sorption and RG (0.7) > BG (0.4) > GA (0.2), GG (0.2), GrG (0.2) for Eu sorption to the different granitic rocks. Values in brackets represent the ratio of Rd-predicted/Rd-calculated. Results from the application of the CAM showed it was not possible to predict the Rd of the bulk sample from the component minerals. Desorption studies at constant pH were analysed by calculating the hysteresis H. The results showed that the higher the Rd the higher the hysteresis. Surface complexation using JChess Geochemical Code was used to obtain surface complexation parameters for the metal-solid complex for sorption in variable pH and constant metal concentration. Experimental data were described by the mass action law to obtained proton stoichiometry at which the sorption edge is defined. Results showed the presence of NaCl decreased the sorption of Ni, and increased the sorption of Eu. Sorption kinetics experiments in different carbonate complexing environments were carried out to study the effect of carbonate on Eu sorption capacity and rate of sorption. Data were fitted to first and second order kinetic models to investigate the sorption rates. Results showed the sorption to be fast initially before reaching a steady state after more than 200 hours of equilibration. Kinetic data confirmed the low sorption capacity observed for quartz. Data obtained for sorption in a mixed radionuclide system were modelled using the Linear model and the surface complexation model. The surface complexation constants are correlated to the Rd values obtained from the linear sorption isotherms. Modelling the results using Rdmix and Rdsing showed that sorption was suppressed in a mixed system, with no effect observed for sorption to feldspar in single and mixed systems. Cation exchange capacity (CEC) measurements were undertaken to deduce a correlation between the CEC of powdered rock samples and intact sample using rock beakers developed from the British Geological Survey by applying the Bascomb method in which the pH was buffered to pH 8.1. Normalising the results using the surface area showed that the CEC of the rock beakers was 6 orders of magnitude greater than that of the powdered sample. In the second part, a method for differentiating two or more radionuclides using storage phosphor imaging plates coupled with the Storm Scanner system was tested. Initial results showed that it is possible to differentiate one radionuclide from another in a mixed system using different levels of shielding.

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Hammarlund, Pär. "Simulation and Analyis of a Continuous Variable Cam Phasing Internal Combustion Engine." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-12170.

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The development of fuel efficient internal combustion engines (ICE)have resulted in a variety of different solutions. One of those are the variable valve timing and an implemenation of such is the Continuous Variable Cam Phasing (CVCP). This thesis have used a simulation package, psPack, for the simulation of the gas exchange process for an ICE with CVCP. The purpose of the simulations was to investigate what kind of design parameters, e.g. the length of an intake pipe or the duration of combustion, that were significant for the gas exchange process with the alternation of intake pressure, engine speed and valve setting. The parameters that showed a vast impact were those who affected the amount of residual gas and the temperature of the air charge. Furthermore a validation was made between simulation data acquired from psPack and measured data provided in Heywood (1988). The validation showed that for the general behaviour the simulation results from psPack corresponded well to the measured data.

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KUNDA, SAKETH RAM. "Methods to Reuse CAD Data in Tessellated Models for Efficient Visual Configurations : An Investigation for Tacton Systems AB." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281748.

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Data loss has always been a side effect of sharing 3D models between different CAD systems. Continuous research and new frameworks have been implemented to minimise the data loss in CAD and in other downstream applications separately like 3D visual graphics applications (eg. 3DS Max, Blender etc.). As a first step into this research area, the thesis is an explorative study on understanding the problem of CAD data loss while exchanging models between a CAD application and a visual application. The thesis is performed at Tacton systems which provides product configurations to their customers in both CAD and visual environments and hence the research is focussed on reusing the CAD data in visual applications or restoring the data after exchange. The research questions are framed to answer the reasons of data loss and address the possible implementation techniques at the company. Being a niche topic, the thesis required inputs from different perspectives and knowledge sharing from people outside the company which proves the significance of open innovation in technology-oriented companies. Ten different ideas were brainstormed and developed into concepts to solve the problem of data loss. All the concepts are analysed and evaluated to check the functionality and feasibility of implementing it within the company workflow. The evaluations resulted in different concepts that are capable of solving the research problem. They have also been verified with various people internal and external to the company. The results also highlight the strengths and weaknesses of each of these concepts giving clear instructions to the company on the next steps.
Dataförluster har alltid varit en följd av att dela 3D-modeller mellan olika CAD-system. I forskning har nya metoder utvecklats och implementerats för att minimera dataförlusten i CAD och andra program, som t.ex. visuella 3D-grafikapplikationer (3DS Max, Blender etc.). Denna rapport är resultatet av en studie kring CAD-dataförluster när man överför modeller mellan ett CAD-program och ett visualiseringsprogram. Studien har utförts vid Tacton Systems AB, som tillhandahåller produktkonfigureringslösningar både i CAD-program och i visuella miljöer och därför har studien haft fokus på att återanvända eller återskapa CAD-data i visualiseringsprogramvaror. Forskningsfrågorna är inriktade på att hitta orsaker till dataförlusterna och möjliga lösningar för företaget. Eftersom detta är ett högspecialiserat ämne krävde arbetet insatser från olika perspektiv och kunskapsinhämtning från människor också utanför företaget, vilket visar på betydelsen av öppen innovation i teknikorienterade företag. Tio olika idéer togs fram och utvecklades till koncept för att lösa problemet med dataförluster. Alla koncept har analyserats och utvärderats för att bedöma deras funktionalitet och genomförbarhet, för att implementera dem inom företagets arbetsflöde. Utvärderingarna resulterade i sex olika koncept som skulle kunna lösa problemet. Dessa koncept har diskuterats och verifierats med olika personer inom och utanför företaget. Resultatet visar styrkor och svagheter i vart och ett av dessa koncept och ger tydliga rekommendationer till företaget om nästa steg.

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Hagba, Dorbor M. "Can market volume help in predicting share market volatility." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/15043.

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Thesis (MBA)--University of Stellenbosch, 2007.
ENGLISH ABSTRACT: This paper explores a number of statistical models for predicting the daily stock return volatility of an aggregate of all stocks traded on the Johannesburg Stock Exchange (JSE). The study is largely inspired by the work of Chris Brooks (1998). The volume of shares traded might be as important as the change in a market index since substantial price increases and decreases are often accompanied by heavy trading activity. An application of linear and non-linear Granger causality tests highlights evidence of bidirectional causality, although the relationship is stronger from volatility to volume than from volume to volatility. The out-of-sample forecasting performance of various linear and non-linear models of volatility are evaluated and compared. The models are also augmented by the addition of a measure of lagged volume to form more general ex-ante forecasting models. The results indicate that augmenting models of volatility with measures of lagged volume leads only to fairly small improvements in forecasting performance. The report also shows that the Johannesburg Stock Exchange is vulnerable to financial turmoil in other major markets.
AFRIKAANSE OPSOMMING: Hierdie navorsingsverslag verken 'n aantal statistiese modelle vir die vooruitskatting van die daaglikse onbestendigheid in aandeleopbrengste van die totaal van alle aandele wat op die Johannesburgse Aandelebeurs (JSE) verhandel word. Hierdie studie is grotendeels geinspireer deur die werk van Chris Brooks (1998). Die volume aandele wat verhandel word, kan net so belangrik wees soos die verandering in 'n markindeks omdat beduidende prysverhogings en -verlagings dikwels met swaar verhandelingsaktiwiteite gepaard gaan. 'n Toepassing van liniere en nie-liniere Grangeroorsaaklikheidstoetse lewer bewys van tweerigting-oorsaaklikheid, hoewel daar 'n sterker verband van onbestendigheid na volume is, as van volume na onbestendigheid. Die buite-steekproef vooruitskattingsprestasie van verskeie liniere en nie-liniere modelle van onbestendigheid word geevalueer en vergelyk. Die modelle word aangevul deur die byvoeging van gesloerde volumes om meer algemene vooruitskattingsmodelle te vorm. Die resultate dui daarop dat aangevulde modelle van onbestendigheid met sloerings in volume slegs tot betreklik klein verbeteringe in vooruitskattingsprestasie lei. Die resultate dui daarop dat die Johannesburgse Aandelebeurs kwesbaar is vir finansiele turbulensie in ander belangrike markte.

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Dissertations / Theses on the topic 'Na+/Ca2+ exchanger'

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