Dissertations / Theses on the topic 'Respiration'
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Tartes, Urmas. "Respiration rhythms in insects." Tartu : Tartu University Press, 1995. http://catalog.hathitrust.org/api/volumes/oclc/24168516.html.
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Brown, G. C. "Control of mitochondrial respiration." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373265.
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Averill, Rachel Hilary. "Control of leaf respiration." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386736.
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Yang, yi fan, and ye Tang. "Instrument for respiration instruction." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-20164.
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In this project, we use a computer to sense, extract features from the signal,synthesize and control a graphical ball. Our aim is to control children respirationby software, displaying a small ball in a screen. When the child breathes on themicrophone, the ball moves in the display so the doctor will have time/possibilityto listen to the lung with a stethoscope.We used Action Script3.0 to write our project codes. The resulting software isexecuted in (Adobe Inc.trademark software environment) Flash.
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Dwivedi, Padmanabh. "Carbohydrate starvation and plant respiration." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624182.
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Yun, Ik. "Respiration inspiration : espace à vivre." Paris 1, 2008. http://www.theses.fr/2008PA010551.
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Ce qui est en jeu, c' est l' expérience temporelle de l' oeuvre dans laquelle la conscience du spectateur engage sa propre temporalité au moment même ou il en fait l' expérience vécue à la fois physiquement et métaphysiquement. Cette réalité expérimentale dans une certaine durée et un certain espace, comme un événement de la vie est un élément spécifique de notre travail «Sculpture-Installation ». Dans cette idée de l' oeuvre, des spectateurs sont invités dans un espace plein de vitalité et d'imagination. Par conséquent l' espace de l' oeuvre se transforme en un dispositif où les rapports entre l' artiste et Ie spectateur sont plus dynamiques que statiques. Ce type de création concernant l' espace est un effort pour créer une autre réalité, qui soit la métaphore d'une réalité profonde de notre vie, un espace comme lieu d' expérience, comme un dispositif de vie. Cette extension des limites du lieu et de l' espace nous amènera à ces interrogations: l' oeuvre est-elle pour le spectateur un objet qui anime le lieu, ou est -ce l' espace qui est modifié par la présence d' un objet artistique ? Le but de notre thèse est de se livrer à une recherche sur la production artistique concernant la problématique de l' espace et de l' oeuvre, et l' expérience temporelle du spectateur. La question de l' « habitation» de l' oeuvre consiste à proposer en un lieu des itinéraires multiples, le long desquels alternent objets naturels et objets issus des nouvelles technologies.
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Raihani, Nilgoun. "Respiration Pattern Using Amplified Video." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case151272961173245.
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Dorrien, Christian F. von. "Ökologie und Respiration ausgewählter arktischer Bodenfischarten = Ecology and respiration of selected Arctic benthic fish species /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1993. http://www.gbv.de/dms/bs/toc/127460144.pdf.
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Smedja, Bäcklund Anna. "Electron transport in microbial chlorate respiration." Licentiate thesis, Karlstad University, Faculty of Technology and Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-3777.
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Several bacterial species are capable to use perchlorate and/or chlorate as an alternative electron acceptor in absence of oxygen. Microbial respiration of oxochlorates is important for biotreatment of effluent from industries where oxochlorates are produced or handled. One of these species, the Gram-negative Ideonella dechloratans, is able to reduce chlorate but not perchlorate. Two soluble enzymes, chlorate reductase and chlorite dismutase, participate in the conversion of chlorate into chloride and molecular oxygen. The present study deals with the electron transport from the membrane-bound components to the periplasmic chlorate reductase. Soluble c cytochromes were investigated for their ability to serve as electron donors to chlorate reductase. The results show that a 6 kDa c cytochrome serves as electron donor for chlorate reductase. This cytochrome also serves as electron donor for a terminal oxidase in the reduction of oxygen that is produced in the course of chlorate respiration. A gene encoding a soluble c cytochrome was found in close proximity to the gene cluster for chlorate reduction. This gene was cloned and expressed heterologously, and the resulting protein was investigated as a candidate electron donor for chlorate reductase. Electron transfer from this protein could not be demonstrated, suggesting that the gene product does not serve as immediate electron donor for chlorate reductase.
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Khamnei, S. "Some factors affecting respiration in man." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258344.
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Painter, R. "Some factors affecting respiration in man." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382599.
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Bascom, Daphne Ayn. "Some factors affecting respiration in man." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302877.
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Newman, Dianne Katherine 1971. "Microbial respiration and precipitation of arsenic." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/40246.
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AGOPIAN, VALERIE. "Oxygene, respiration et altitude : revue generale." Aix-Marseille 2, 1993. http://www.theses.fr/1993AIX20133.
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Borgelt, Jan. "Terrestrial respiration across tundra vegetation types." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-132765.
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Large amounts of carbon (C) are stored in tundra soils. Global warming may turn tundra ecosystems from C sinks into sources or vice versa, depending on the balance between gross primary production (GPP), ecosystem respiration (ER) and the resulting net ecosystem exchange (NEE). We aimed to quantify the summer season C balance of a 27 km2 tundra landscape in subarctic Sweden. We measured CO2 fluxes in 37 widely distributed plots across five tundra vegetation types and in 7 additional bare soil plots, to assess effects of abiotic and biotic components on C exchange. C fluxes in bare soils were low and differed to all vegetation types. Thus, accounting for differences between bare soils and vegetated parts is crucial for upscaling a C balance using a landcover classification map. In addition, we found that both NEE and ER, varied within and across different tundra vegetation types. The C balance model for the growing season 2016 revealed a net C loss to the atmosphere. Most vegetation types acted as CO2 sources, with highest source strength in dense shrub vegetation at low elevations. The only considerable C sinks were graminoid-dominated upland meadows. In addition, we found a shift in C balance between different heath vegetation types, ranging from C source in dense deciduous shrub vegetation (Mesic Heath and Dry Heath) to C sink in low growing shrub vegetation (Extremely Dry Heath). These results highlight the importance to account for differences between vegetation types when modelling C fluxes from plot to landscape level.
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Smedja, Bäcklund Anna. "Electron transport in microbial chlorate respiration /." Karlstad : Faculty of Technology and Science, Chemistry, Karlstads University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-3777.
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Bruhn, Dan. "Plant respiration and climate change effects." Roskilde : Risø National Laboratory, 2002. http://www.risoe.dk/rispubl/PRD/prdpdf/ris-r-1332.pdf.
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Promayon, Emmanuel. "Modélisation et simulation de la respiration." Phd thesis, Grenoble 1, 1997. https://theses.hal.science/tel-00130070.
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Le problème de la modélisation et de la simulation des mouvements du tronc pendant la respiration est étudié dans cette thèse. L'objectif est la représentation graphiquement réaliste de ces mouvements grâce à des modèles générateurs. Le découpage de ce document propose des étapes méthodologiques pour la modélisation. Dans une première partie les principes mécaniques du phénomène de la respiration sont exposés. Le problème apparaît alors comme la modélisation et la simulation comportementale sous contraintes d'un objet complexe composés de régions ayant des propriétés différentes (élasticité, motricité, rigidité). Les modèles générateurs basés sur la physique se révèlent être les outils informatiques les plus aptes à atteindre notre objectif. Un état de l'art de ces méthodes et des problématiques liées est alors dressé. La deuxième partie présente la construction du modèle informatique découpée en régions de propriétés spécifiques. On présente alors une nouvelle fonction d'élasticité utilisant l'expression d'une mémoire de forme locale. Comparée à un modèle classique masse-ressort, cette fonction d'élasticité prouve son efficacité. La modélisation des régions musculaires et solides est ensuite présentée. Puis, on montre la possibilité de contraindre ces régions afin de modéliser d'autres propriétés. On développe notamment une méthode de résolution directe permettant de vérifier des contraintes locales et globales sans utiliser d'algorithme itératif. La résolution de la contrainte d'incompressibilité illustre cette méthode de résolution ; les principes généraux de cette résolution sont dégagés permettant ainsi de généraliser son application. La dernière partie de ce manuscrit fournit une validation qualitative du modèle développé par l'intermédiaire de différents exemples, dont celui de la simulation des mouvements du tronc pendant la respiration.
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Promayon, Emmanuel. "Modélisation et Simulation de la Respiration." Phd thesis, Université Joseph Fourier (Grenoble), 1997. http://tel.archives-ouvertes.fr/tel-00130070.
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Le problème de la modélisation et de la simulation des mouvements du tronc pendant la respiration est étudié dans cette thèse. L'objectif est la représentation graphiquement réaliste de ces mouvements grâce à des modèles générateurs. Le découpage de ce document propose des étapes méthodologiques pour la modélisation.Dans une première partie les principes mécaniques du phénomène de la respiration sont exposés. Le problème apparaît alors comme la modélisation et la simulation comportementale sous contraintes d'un objet complexe composés de régions ayant des propriétés différentes (élasticité, motricité, rigidité). Les modèles générateurs basés sur la physique se révèlent être les outils informatiques les plus aptes à atteindre notre objectif. Un état de l'art de ces méthodes et des problématiques liées est alors dressé.
La deuxième partie présente la construction du modèle informatique découpée en régions de propriétés spécifiques. On présente alors une nouvelle fonction d'élasticité utilisant l'expression d'une mémoire de forme locale. Comparée à un modèle classique masse-ressort, cette fonction d'élasticité prouve son efficacité. La modélisation des régions musculaires et solides est ensuite présentée. Puis, on montre la possibilité de contraindre ces régions afin de modéliser d'autres propriétés. On développe notamment une méthode de résolution directe permettant de vérifier des contraintes locales et globales sans utiliser d'algorithme itératif. La résolution de la contrainte d'incompressibilité illustre cette méthode de résolution ; les principes généraux de cette résolution sont dégagés permettant ainsi de généraliser son application.
La dernière partie de ce manuscrit fournit une validation qualitative du modèle développé par l'intermédiaire de différents exemples, dont celui de la simulation des mouvements du tronc pendant la respiration.
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Iost, Susanne. "Soil respiration, microbial respiration and mineralisation in soils of montane rainforests of Southern Ecuador: influence of altitude." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1201126765623-42870.
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Impacts of land use and climate change in tropical forests on the global carbon budget are of principal interest in the recent research, as these forests amount to about 48 % of the world’s forested area. Interest has been focused on lowland tropical forests mainly, but tropical montane forests occupy about 20 % of all tropical forests. Soils of tropical montane forests are frequently waterlogged and characterised by high soil organic carbon stocks. Furthermore, along altitudinal gradients, changes in stand structure and net primary production can be observed that have not been fully explained yet. As causes reduced microbial activity and nitrogen turnover in soils of tropical montane forests have been suggested. Against the background of climate change, carbon turnover mechanisms in soils of these forests are of special interest. The present study therefore aimed at determining and quantifying relevant carbon and nitrogen pools as well as nitrogen mineralisation potentials. Furthermore, size, activity, and structure of microbial biomass were characterised. The collected data was supposed to provide basic knowledge on carbon and nitrogen cycling in tropical montane forest soils. Thus, evaluation of the susceptibility of their carbon stocks for climate change as well as nitrogen and carbon limitation of microbial organic matter decomposition was possible. Field work of this study was conducted during 2003–2005 at an altitudinal transect that in- cluded five study sites between 1 050 and 3 060 m amsl. Total soil respiration was recorded biweekly over two years, the contribution of roots to total soil CO2 efflux over one year. Soils of the study sites were sampled twice and biochemical and microbial parameters were determined.
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Xue, Xiaoping. "Interactions between photosynthesis and respiration in the green alga Chlamydomonas reinhardtii, characterization of light-enhanced dark respiration." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0002/NQ30264.pdf.
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Iost, Susanne. "Soil respiration, microbial respiration and mineralisation in soils of montane rainforests of Southern Ecuador: influence of altitude." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A24042.
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Impacts of land use and climate change in tropical forests on the global carbon budget are of principal interest in the recent research, as these forests amount to about 48 % of the world’s forested area. Interest has been focused on lowland tropical forests mainly, but tropical montane forests occupy about 20 % of all tropical forests. Soils of tropical montane forests are frequently waterlogged and characterised by high soil organic carbon stocks. Furthermore, along altitudinal gradients, changes in stand structure and net primary production can be observed that have not been fully explained yet. As causes reduced microbial activity and nitrogen turnover in soils of tropical montane forests have been suggested. Against the background of climate change, carbon turnover mechanisms in soils of these forests are of special interest. The present study therefore aimed at determining and quantifying relevant carbon and nitrogen pools as well as nitrogen mineralisation potentials. Furthermore, size, activity, and structure of microbial biomass were characterised. The collected data was supposed to provide basic knowledge on carbon and nitrogen cycling in tropical montane forest soils. Thus, evaluation of the susceptibility of their carbon stocks for climate change as well as nitrogen and carbon limitation of microbial organic matter decomposition was possible. Field work of this study was conducted during 2003–2005 at an altitudinal transect that in- cluded five study sites between 1 050 and 3 060 m amsl. Total soil respiration was recorded biweekly over two years, the contribution of roots to total soil CO2 efflux over one year. Soils of the study sites were sampled twice and biochemical and microbial parameters were determined.
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McKenzie, David J. "Ventilation in Amia calva : a comparison with water-breathing fish." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30654.
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Aspects of ventilation and ventilatory control were investigated in an air-breathing fish, Amia calva, to determine the extent to which Amia is similar to water-breathing fish.
The possibility that Amia uses the air-breathing organ to maintain gas-exchange during periods of aestivation was tested. During gradual air-exposure, Amia showed no reduction in oxygen consumption, no increase in plasma urea levels or in urea excretion. Arterial blood pH (pHa) remained constant, and arterial plasma total carbon dioxide (TaCO₂) and carbon dioxide partial pressure (PaCO₂) increased. Arterial plasma total ammonia (Tamm) and NH₃ concentrations rose significantly. Exposure to elevated total ammonia concentrations in the water did not elicit an increase in urea production or air-breathing. Aquatic hypoxia without access to air did not cause a reduction in aerobic metabolism and moderate levels were fatal. These results indicate that Amia are incapable of aestivation, due to an inability to reduce metabolism and detoxify ammonia to urea, and die following three to five days of air-exposure. The air-breathing organ is used to maintain aerobic metabolism under aquatic conditions of hypoxia or raised temperature.
The characteristics of air-breathing and gill ventilatory responses to internal acid-base disturbances were investigated in Amia. Acid infusions lowered pHa and arterial blood oxygen content (CaO₂), raised PaCO₂, and stimulated air-breathing and gill ventilation. Ammonium bicarbonate infusions did not change pHa or CaO₂, raised PaCO₂, and did not stimulate any ventilatory responses. Acid infusions during aquatic hyperoxia lowered pHa and raised PaCO₂. Arterial blood O₂ content declined but remained above normoxic levels. There were no ventilatory responses. These results indicate that air-breathing and gill ventilation responses in Amia are most closely correlated with blood O₂ status, not pHa or PaCO₂. Air-breathing and gill ventilation responses following acid infusion were associated with a release of catecholamines into circulation. Catecholamine infusion stimulated gill ventilation but not air-breathing in Amia, suggesting that endogenous catecholamine release may have mediated gill ventilatory responses to hypoxaemia. These ventilatory reflex responses to acid-base disturbance, and the correlation between gill ventilation responses and catecholamine release are similar to observations made on water-breathing fish.
Ventilatory responses to increases in TaCO₂ and Tamm were investigated in rainbow trout, and compared with responses by Amia. In trout, infusion of NaHCO₃ raised pHa and TaCO₂, did not change PaCO₂ or CaO₂, and stimulated ventilation. Infusion of NH₄HCO₃ did not change pHa or CaO₂, raised TaCO₂, PaCO₂ and Tamm, and stimulated ventilation. Infusion of NH₄Cl lowered pHa, raised Tamm, and stimulated ventilation. Infusion of HCl lowered pHa, TaCO₂ and CaO₂, and stimulated ventilation. Infusion of NaOH raised pHa but did not stimulate ventilation until twenty minutes post-infusion. Infusion of NaCl had little or no effect on pHa, CaO₂, TaCO₂ or Tamm, and no effect on ventilation. These results indicate that trout show a ventilatory response to increases in TaCO₂, increases in Tamm and decreases in pHa and CaO₂, but not to increases in pHa. Following HCl and NaHCO₃ infusion, there was a significant increase in the level of circulating catecholamines, indicating that the ventilatory responses to reductions in pHa and CaO₂ and increases in TaCO₂ may be Immorally mediated by catecholamine release. The ventilatory responses to increases in Tamm were not associated with a catecholamine release. Unlike trout, Amia do not show a ventilatory response to infusion of NH₄HCO₃, i.e. to increases in TaCO₂ and Tamm.
Sites and afferent pathways for ventilatory reflex responses to blood and water O₂ status were determined in Amia. Air-breathing and gill ventilatory reflex responses to hypoxia, sodium cyanide (NaCN), hypoxaemia and catecholamines were investigated in intact Amia, and compared with responses in animals following section of branchial branches of cranial nerves IX and X, and extirpation of the pseudobranch. In intact, sham-operated animals, hypoxia stimulated an increase in air-breathing and gill ventilation. Following denervation, the air-breathing response was abolished, and the gill ventilation response significantly attenuated. In sham-operated animals, NaCN in the water flowing over the gills stimulated air-breathing and gill ventilation, and NaCN given in the dorsal aorta stimulated gill ventilation. These responses were abolished following denervation. In intact animals, HC1 infusion stimulated air-breathing and gill ventilation, but following denervation, the air-breathing response was abolished. The ventilatory response to catecholamines was significantly attenuated in denervated animals as compared with shams. These results indicate that air-breathing and gill ventilation reflex responses are controlled by oxygen-sensitive receptors in the gills and pseudobranch, innervated by cranial nerves VII, IX and X. These sites and afferent pathways are similar to receptors controlling hypoxic reflex responses in water-breathing fish. The effects of catecholamines on gill ventilation are mainly exerted via stimulation of receptors in the gills, which are separate from those controlling air-breathing. The gill ventilatory responses to hypoxia, hypoxaemia and acidosis following denervation may be mediated by central effects of circulating catecholamines, or by an extrabranchial oxygen or pH receptor.
In conclusion, Amia is an entirely aquatic animal with the primary ventilatory control mechanisms of water-breathing fish intact, but with the added ability to breathe air at the surface.Science, Faculty of
Zoology, Department of
Graduate
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Foulds-Elliott, Susannah Deborah. "Respiration in operatic singing: Intention to communicate." University of Sydney. Communication Sciences and Disorders, 2004. http://hdl.handle.net/2123/657.
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Professional operatic singing can be performed technically for practice and rehearsal, or with heightened emotion through intention to communicate with an audience. Previous studies of respiration in operatic singing have not taken into account the professional performer�s ability to differentiate at will between rehearsal and performance modes of singing. The aim of this thesis is to investigate the differences between singing �with intention to communicate� (as if performing) and singing �technically� (as if in rehearsal). The hypothesis is that this specified change of condition would change the respiratory patterns employed by the singers. Estimation of respiratory patterns was obtained using magnetometers. Performance singing was labelled �IC� (intention to communicate). Rehearsal singing was labelled �T� (technical) and also included �TL� (technical loud) and �TS� (technical soft). Each of the five singers performed two tasks (a free choice aria in Italian, and a set song). Only intra-subject analysis was used. One thousand and one breaths were analysed. These were then matched, so that only complete musical phrases (sung six times by the same singer) were compared with each other. Seven hundred and sixty-two matched phrases were analysed in this way. Measured variables were initiation lung volume (ILV), termination lung volume (TLV), the amount of lung volume expired (LVE), %VC released per second (Flow), the expiratory time (Te), and inspiratory time (Ti). Sound pressure level (SPL) was measured. This study also examined the ability of experienced listeners to distinguish between the T and IC performances from DAT recordings. Findings show that in comparison with T singing, IC singing used more air, with a greater percentage of vital capacity expired per second, but without a simple association with sound pressure level or expiratory time. Listeners were able to distinguish IC from T performances, demonstrating a perceived difference in the quality of the vocal output. These results demonstrate that performance intention to communicate, compared to rehearsal, results in a measurable difference in respiratory parameters, and therefore needs to be specified in future research.
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Denton, Laura Elaine Scott. "Soil respiration at a Colorado subalpine forest." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/dissertations/fullcit/3165811.
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Stewart, Heather 1971. "Partitioning belowground respiration in a northern peatland." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98806.
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To further the understanding of respiration processes of northern peatlands, the relative importance of each type of belowground respiration was determined at Mer Bleue, a northern peatland located near Ottawa, Ontario, from June to November, 2003. Direct measurements of total, soil organic matter (SOM) and root respiration were made, with rhizosphere respiration determined by residual. Although an aboveground source, determination of live Sphagnum respiration was also attempted in the field. To identify changes in CO2 fluxes with environmental conditions, peat temperature and water table levels were monitored throughout the study period.SOM respiration was higher than hypothesized at 63% while root and rhizosphere respiration were lower than hypothesized at 21% and 16%, respectively, of total belowground respiration. As the field experiment for determining live Sphagnum respiration was unsuccessful, it was determined by calculation to be 18% of total respiration, slightly higher than hypothesized. Opposite of hypothesized, air temperatures, peat temperatures and water table levels generally had weak and insignificant relationships when linearly regressed with total respiration.
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Tang, Evonne P. Y. (Evonne Pui Yue). "The allometry of algal growth and respiration." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22815.
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A knowledge of the allometry of algal growth and respiration can be applied to biomass-size distribution models which are in turn used in the prediction of fish yield and ecosystem studies. However, the scaling exponents reported in the literature are variable. This variation may be attributed to differences in the expression of cell size and phylogeny, but could also reflect small sample size which underlie most published regressions. This thesis establishes the allometry of algal growth and respiration based on a larger sample taken from the literature, and evaluates the effects of differences in gross taxonomy and in the expression of cell size on these relations. Allometric relations based on cell carbon appear more consistent with relations from other taxa than those based on cell volume, reflecting the size dependence of algal elemental composition which does not occur in most other taxa. The allometric relation of algal respiration (R in pl O$ rm sb2 cdot cell sp{-1} cdot hr sp{-1})$ was found to be R = 0.030C$ sp{0.93}$ where C is cell carbon content in pg C$ rm cdot cell sp{-1}$. Among the 6 divisions studied (Chlorophyta, Chrysophyta, Cyanophyta, Euglenophyta, Pyrrophyta, Rhodophyta), chlorophytes, euglenophytes and rhodophytes exhibited different respiration-size relation but separate relations were not developed for each of those groups due to patterns in residuals or small sample sizes. The specific rate of algal growth ($ mu$ in divisions$ cdot$day$ sp{-1}$) also depends on size and it is found to be $ mu$ = 3.45C$ sp{-0.21}.$ All taxa studied here (Chlorophyta, Chrysophyta, Pyrrophyta) have similar scaling exponents for growth but Pyrrophyta have significantly lower growth rates than other algae of similar size.
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Hartley, Iain P. "The response of soil respiration to temperature." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434021.
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Park, Hyesung Ph D. Massachusetts Institute of Technology. "Fabrication of microfluidic devices for artificial respiration." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40370.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (p. 101-108).
We are developing elastomeric polydimethylsiloxane (PDMS) microfluidic devices incorporated with photoactive thin films to create an implantable artificial respiration platform. Whereas state-of-the-art respiration support machines deliver oxygen gas directly to the blood via external macroscale devices, our technique utilizes a biomimetic photocatalytic process to generate energy from light and thus produce dissolved oxygen from water which is already present in the blood. Blood oxygenation will be achieved by the interaction between the photoactivated metal oxide film and blood in the setting of a molded microfluidic conduit, providing a stable and implantable oxygenation platform. As a basic, scalable building block, we developed a noble "network" design which was structurally similar to the native pulmonary capillary network. The interconnected channel geometry was designed in such a way to minimize shear stress and reduce hemolysis and thrombosis inside the microchannel. It allowed alternative flow pathways in the event of single channel occlusion while minimizing the establishment of detrimental pressure gradients. The hemocompatibility analysis demonstrated that the network construct showed acceptable levels of hemolysis rate (< 8%) and thrombus formation.
(cont.) Critical to the success of this project is the understanding of the manufacture parameters for microfluidic devices molded from elastomeric materials like PDMS. In the initial development of our work, we performed the following three tasks to generate manufacture protocols for elastomeric microfluidic devices that will be ultimately used for biological applications: 1) Curing schedules of the heat-cure PDMS elastomers under various fabrication parameters were characterized. 2) The interlayer bonding chemistry of the double layer PDMS device was analyzed followed by subsequent mechanical analysis. 3) The efficacy of various surface treatment techniques on hydrophobic PDMS surfaces was investigated using fluorescently tagged bacteria (E. Coli) flowed through microchannels as reporter particles to measure non-specific adhesion, which will provide useful information in minimizing channel fouling for biological applications.
by Hyesung Park.
S.M.
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Fieldstone, Annette. "Respiration as a mediator of body temperature /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu148819950140483.
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Moulin, Kevin. "Imagerie de diffusion cardiaque en respiration libre." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1007/document.
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L'imagerie par résonance magnétique (IRM) de diffusion est une technique permettant de sensibiliser un signal de résonance magnétique au mouvement brownien des molécules d'eau. Cette méthode a été utilisée pour accéder à l'information structurelle des tissus en neurologie et est devenu un outil crucial de prise en charge des patients à la phase aigüe de l'accident vasculaire cérébral pour la détection de la zone d'ischémie cérébrale. Il est pressenti que de disposer de ce type d'imagerie en cardiologie pourrit compléter avantageusement les outils d'IRM cardiaque pour le diagnostic de pathologie cardiovasculaire courantes, à la phase aigüe ou chronique de l'infarctus du myocarde mais aussi pour le suivi de toutes cardiomyopathies. Cependant cette technique, sensible au mouvement des molécules d'eau, est confrontée en cardiologie aux mouvements cardiaques et respiratoires. Les méthodes présentées actuellement dans la littérature pour faire face à ces mouvements nécessitent des temps d'acquisition considérables et donc incompatible avec une application clinique de l'IRM de diffusion en cardiologie. L'objectif de la thèse est de développer l'IRM de diffusion cardiaque compatible avec les contraintes clinique pour en permettre le transfert vers une application en routine clinique. Notre travail s'est tout d'abord concentré sur le développement d'une technique séquence et d'une stratégie d'acquisition en respiration libre permettant une acquisition continue pendant toute la totalité du cycle respiratoire. Cette séquence de diffusion, utilise l'écho navigateur, image 1D fournissant prospectivement l'information de position de l'interface foie/poumon en temps réel, pour adapter en temps réel la position de coupe en fonction de la phase respiratoire, permettant ainsi de compenser le déplacement tête-pied du coeur induit par la respiration. Cette méthode appelé « slice-following » a été validée pour l'imagerie de diffusion cardiaque dans une étude de reproductibilité conduite sur 10 volontairesDiffusion magnetic resonance imaging is a technic allowing a sensitization of the magnetic resonance signal to Brownian motion of water molecules. This method was used to probe structural information of tissue in neuroimaging and became a tool of paramount importance in the management of patient with acute cerebral vascular accident for the detection of ischemic cerebral zone. The motivation is high to develop diffusion magnetic resonance imaging in cardiology which could complete actual cardiac MR method for the diagnostic of acute infarct or myocarditis. However this technique is very sensitive to motion and face in cardiology to breathing and cardiac motion. Until now, the methods proposed to take care of these motions increased considerably the scan time and are not compatible with clinical constraints. The aim of this thesis is to develop cardiac diffusion magnetic resonance imaging compatible with such constraints which could be used for clinical applications. We proposed a new approach of free-breathing technique allowing scanning during all the respiratory cycle. This new diffusion sequence is based on echo navigator, a 1D image given prospectively and in real time the lung/liver interface. The information given by the navigator is used to adapt the slice position according to breathing phase in real time. This method called “slice-following” correct the head foot displacement of the heart induced by the breathing and was validated on a reproducibility study on 10 volunteers
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Foulds-Elliott, Susannah. "Respiration in operatic singing intention to communicate /." Connect to full text, 2004. http://hdl.handle.net/2123/657.
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Thesis (Ph. D.)--University of Sydney, 2005.Title from title screen (viewed 19 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Communication Sciences and Disorders, Faculty of Health Sciences. Degree awarded 2005; thesis submitted 2004. Includes bibliographical references. Also available in print form.
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Liang, Yuanxin. "Respiration monitoring with a fibre optic sensor." Swinburne Research Bank, 2008. http://hdl.handle.net/1959.3/47121.
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Thesis (PhD) - Swinburne University of Technology, Faculty of Engineering and Industrial Sciences, Centre for Atom Physics an Ultra-fast Spectroscopy, 2008.A thesis submitted for the degree of Master of Engineering, Centre for Atom Physics an Ultra-fast Spectroscopy, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, 2008. Typescript. Bibliography: p. 143-149.
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Lecomte, Solène. "Anaerobic respiration diversification in Agrobacterium fabrum C58." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1231.
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La respiration anaérobie peut être un trait essentiel dans le mode de vie, la colonisation de l'environnement et la survie. Jusqu'à présent, la seule respiration anaérobie confirmée chez Agrobacterium spp. est la dénitrification. De façon intéressante, cette voie est inégalement répandue chez les agrobactéries. Ces observations m'ont amené à mon hypothèse, à savoir la respiration anaérobie et notamment la dénitrification pourraient expliquer la coexistence d'agrobactéries et leur distribution dans des niches spécifiques de la rhizosphère. Ma thèse visait à explorer les stratégies de respiration anaérobie d’Agrobacterium spp. et de les relier à l'adaptation de niche écologiques différentes. Les objectifs de ma thèse étaient (1) de caractériser tous les gènes impliqués dans la dénitrification chez A. fabrum C58 in vitro, (2) d'explorer les gènes de la dénitrification nécessaires à la colonisation des racines du maïs et (3) de découvrir de nouvelles respirations anaérobies pendant la colonisation racinaire du maïs (Figure 16). Réaliser des mutants et les tester dans des conditions particulières est le moyen classique de déterminer l'implication d'un gène dans une voie spécifique. Cependant, cette méthode implique une vision à priori et des connaissances solides sur les gènes cibles et ne peut pas être appliquée à toutes les situations. Nous avons alors dû développer une méthode plus adaptée pour identifier les gènes essentiels impliqués dans la croissance dans des conditions anaérobies spécifiques. - Gènes de dénitrification chez A. fabrum C58 in vitro. Pour compléter la voie de dénitrification chez A. fabrum C58 et identifier tous les gènes et régulateurs impliqués dans la dénitrification, nous avons adopté deux stratégies : Premièrement, une vision à priori pour (1) identifier la nitrate réductase impliquée dans la première étape de la dénitrification et (2) valider le rôle d'un ARN non codant dans le contrôle de la dénitrification. Pour ce faire, nous avons construit un mutant napA de A. fabrum C58 et un mutant de l'ARN non codant NopR et nous avons évalué leur croissance et leur capacité à produire du N2O dans des conditions anoxiques. Deuxièmement, pour identifier tous les gènes impliqués dans la dénitrification, nous avons construit une banque de transposons mutants de C58 et testé sa croissance dans des conditions de dénitrification in vitro en présence de nitrate ou de nitrite. - Rôle des gènes de la denitrification de A. fabrum C58 dans la colonisation racinaire du maïs. Il est bien connu que le séquençage de transposons (Tn-Seq) est une méthode très puissante pour déterminer les gènes nécessaires à la croissance bactérienne en présence de leur hôte. Pour déterminer les gènes de dénitrification impliqués dans la colonisation des racines en anoxie, nous avons utilisé la banque construite chez C58 et l’avons inoculée sur les plants de maï cultivées sur un sol fertile et cultivées dans des conditions inondées mimant des conditions anaérobies. Le séquençage des cellules d ‘A. fabrum C58 récupérées mettra en évidence les gènes impliqués dans la colonisation anaérobie de cette niche spécifique. - Découverte de nouvelles voies de respiration anaérobie chez A. fabrum C58. Pour découvrir de nouvelles voies de respiration anaérobie, nous avons mis en place des tests de croissance de C58 dans des conditions anoxiques en présence de sources de C et de N en tant qu'accepteurs terminaux d'électrons. De façon interéssante, en cultivant des souches WT et mutée dans le gène napA au contact de la racine de maïs dans des conditions anoxiques (chapitre 1), nous avons montré une croissance des deux souches. Ce résultats suggère que les exsudats de racine servent d'accepteurs d'électrons terminaux pour la croissance anaérobie de C58. Pour déterminer quels composés exsudés du maïs peuvent servir de TEA, les principaux métabolites ont été identifiés par HPLC et certains ont été testés en tant que TEA dans des conditions anoxiquesAnaerobic respiration may be an essential trait in lifestyle, environment colonization and survival. Until now, the only confirmed anaerobic respiration in Agrobacterium spp. is denitrification. Interestingly, this pathway is unequally widespread among Agrobacteria. These observations led me to my hypothesis which is anaerobic respiration and notably denitrification could explain the coexistence of Agrobacteria and their distribution in specific niches in the rhizosphere. My thesis was undertaken to explore the anaerobic respiration strategies of Agrobacterium spp. and to relate them to niche adaptation. The objectives of my thesis were to (1) characterize all the genes involved in denitrification in A. fabrum C58 in vitro, (2) explore the genes of denitrification that are needed during maize root colonization and (3) discover new anaerobic respirations that occur during maize root colonization (Figure 16). Mutational analysis is the classic way to determine the involvement of a gene in specific pathway. However, this method implies an a priori view and solid knowledge on target genes and cannot be applied for every situation. We have to develop a more adapted method to identify essential genes involved in growth in specific anaerobic conditions. - Denitrification genes in A. fabrum C58 in vitro. To complete denitrification pathway in A. fabrum C58 and identify all the genes and regulators involved in the denitrification function, we adopted two strategies: Firstly, an a priori view to (1) identify the nitrate reductase involved in the first step of denitrification and (2) validate the role of a non-coding RNA in denitrification control. To do so, we constructed a mutant of napA of A. fabrum C58 and a mutant of the non-coding RNA NopR and we evaluated their growth and capacity to produce N2O under anoxic conditions. Secondly, to identify all the genes involved in denitrification, we constructed a mutant transposon library of C58 and tested its growth under denitrification conditions in vitro in the presence of either nitrate or nitrite. - Role of A. fabrum C58 denitrifying genes in the root colonization of maize. It is well known that Transposon-sequencing (Tn-Seq) is a very powerful method to determine genes required for bacterial growth in the presence of their host. To determine denitrifying genes involved in root colonization under anaerobic conditions, we used the library constructed in C58 and performed in planta assays. The mutant library was inoculated on maize plants grown on fertile-ground and cultured under flooded conditions miming anaerobic conditions. Sequencing the recovered A. fabrum C58 cells will evidence the genes involved in this anaerobically specific niche colonization. - Discovery of new anaerobic respiration pathways in A. fabrum C58. To discover new anaerobic respiration pathways, we set-up growth assays of C58 under anoxic conditions in the presence C and N sources as terminal electrons acceptors. Interestingly, by culturing WT and NapA-deficient strains in contact with maize root under anoxic conditions (Chapter 1), we showed growth of both strains, suggesting that root exudates serve as terminal electrons acceptors for anaerobic growth of C58. To determine which maize exuded compounds can serve as TEAs, primary metabolites were identified by HPLC and some were tested as TEAs under the set-up conditions
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Fennessey, Christine Michelle. "A novel mode of bacterial respiration: iron solubilization prior to electron transfer." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37257.
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Microbial iron respiration contributes significantly to the biogeochemical cycling of metals and may be one of the earliest respiratory processes to have evolved on early earth. Metal-respiring microbes also hold great potential for use in microbial fuel cells for the generation of "green" energy and for remediation of radionuclides in contaminated environments. Despite its significance in global metal cycling processes, the molecular mechanism of Fe(III) respiration has yet to be determined. Unlike many other terminal electron acceptors, Fe(III) is a solid at circumneutral pH and, therefore, cannot come into direct contact with the microbial inner membrane: the site of terminal electron transfer in gram-negative bacteria. It is postulated that metal-respiring organisms have developed alternate strategies for the reduction of solid iron. One such strategy involves the production of an Fe(III)-solublizing ligand by the metal-respiring bacteria which solubilizes the Fe(III) prior to respiration, rendering the metal more easily accessible to the Fe(III) reductase complex.
In this study, the genes involved in the solubilization of Fe(III) by the gram-negative dissimilatory metal reducing bacteria Shewanella oneidensis MR-1 were determined using random mutagenesis to generate mutations in the wild-type genome and high-throughput square-wave voltammetry to screen for the attenuation of Fe(III) production in the mutants. Two mutants unable to solubilize Fe(III) were identified and designated d29 and d64. After mutation complementation analysis, it was determined that the point mutations were both located in type II secretion genes: gspG and gspE respectively, indicating that the type II secretion system is required for Fe(III) solubilization prior to respiration.
It was also hypothesized that the ligand produced for Fe(III) solubilization during dissimilatory Fe(III) respiration was a siderophore: a small Fe(III)-chelating molecule produced by the cells for the assimilation of Fe(III) for growth. A siderophore biosynthesis gene (SO3031) and a siderophore ferric reductase gene (SO3034) were deleted in frame and the resultant mutants screened to determine whether they were capable of Fe(III) solubilization and reduction during anaerobic Fe(III) respiration. Both mutants retained Fe(III) solubilization and reduction activity, indicating that the siderophore Fe(III) assimilatory system is distinct from the Fe(III) solubilization system utilized during Fe(III) respiration.
The work presented here is significant in that it describes a rapid screening method for identifying Fe(III) solubilization mutants, reports on the involvement of the type II secretion system in Fe(III) solubilization during iron respiration, and finally demonstrates that a dissimilatory metal reducing bacteria synthesizes and secretes Fe(III)-chelating molecules which are distinct from Fe(III)-siderophores.
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Fengler, John Josef Paul. "Respiration induced oxygen gradients in cultured mammalian cells." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28381.
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Oxygen is known to sensitize X-irradiated cells to lethal radiation damage. At low ambient oxygen tensions, however, the molecular mechanisms of the sensitization process and the metabolic requirements of the cell may be forced to compete for the cellular oxygen supply. The effect of cell respiration on the availability of intracellular oxygen during irradiation was consequently investigated by comparing the radiosensitivities of respiring and non-respiring cells. Cultured mammalian cells were irradiated in single cell suspensions and thin film monolayers at respiration inhibiting (4°C) and at normal cell culturing (37°C) temperatures. Due to oxygen equilibration and radiolytic depletion problems, the results of the suspension culture experiments were inconclusive. By subsequently analyzing the diffusive mass transfer of oxygen in the suspension medium, the stirrer flask was determined to be an inappropriate culture vessel in which to irradiate cells at constant low oxygen concentrations. A thin film cell culture system in which the oxygen concentrations to which the cells were exposed during irradiation could be more accurately controlled was then developed. A comparison of the oxygen enhanced radiosensitivities of the respiring and non-respiring cells in thin film monolayers suggested that the metabolic depletion of oxygen at low oxygen tensions has a significant effect on the local and intracellular oxygen distribution. These effects are representative of those that would be produced if respiration induced oxygen gradients existed inside and immediately around respiring cells. The magnitude of the differential radiosensitivities was found to be dependent on cell shape and to have values that agreed very well with theoretical predictions based on the existence of such gradients.Science, Faculty of
Physics and Astronomy, Department of
Graduate
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Derakhshan, Mohammad. "The effect of human viruses on mitochondrial respiration." Thesis, University of Surrey, 2006. http://epubs.surrey.ac.uk/842762/.
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Previous studies have indicated that viruses can interact with mitochondria and affect their function. Further, emerging data now show that many more viruses may influence the mitochondrial pathway of apoptosis and thus there is widespread potential for interaction with the respiratory chain in this organelle. Such interactions could have consequences for the clinical outcome of persistent infections; however it is not known how widespread effects on respiration may be. We have therefore screened different human viruses for an effect on the mitochondrial respiration. We found that human herpes virus type one (HHV-1) and influenza virus (IV) caused a profound decrease in total cell respiration whilst measles virus (MV) and cytomegalovirus (CMV) did not. We have further analysed the integrity of the electron transport chain in the mitochondria of HHV-infected HeLa cells and located a block at complex II; electrons donated to this complex were unable to flow on to complex EL Further investigation revealed that this block was established during the beta phase of HHV-1 protein synthesis. Beta-phase proteins were assessed for potential involvement in this process using the reported literature and a shortlist of candidates was derived. Of these the beta protein Us3 was cloned and expressed by transfection and was found to induce respiratory block in comparison with mock-transfected and luciferase-transfected cells. A mutant deficient in this protein was obtained and shown to be unable of inducing a similar effect. We thus conclude that taxonomically distinct viruses can indeed affect mitochondrial function and virus- specified proteins are responsible. In the case of herpes virus, HHV-1 protein US3 is capable of inducing this effect alone; no other virus proteins are required. Furthermore US3 appears to be the only HHV-1 protein capable of inducing this effect. These findings demonstrate that diverse viruses may induce mitochondrial impairment and this could be a widespread phenomenon. This could underlie the induction of similar features of infection by different viruses and could be significant in the context of a persistent infection.
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Hafner, Roderick Peter. "Thyroid hormone and the control of mitochondrial respiration." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315080.
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Tuffnell, Craig Simon. "Biomedical engineering aspects of infant thermoregulation and respiration." Thesis, University of Canterbury. Electrical and Electronic Engineering, 1993. http://hdl.handle.net/10092/6698.
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Analysis of infant body temperature, environmental temperature and respiratory behaviour has become an important aspect of Sudden Infant Death Syndrome research. The application of engineering techniques as a means of providing research tools has been found to be beneficial for medical research. Signal processing techniques have been developed and applied to the analysis of physiological signals that have been collected from infants in the home environment. These techniques allow physiological signals to be analysed and correlated with the use of both time and frequency domain algorithms. Signals of several days duration are manipulated so they may be easily viewed and studied without the loss of significant information. Parameter evaluation of the fundamental frequencies of periodic signals and statistical parameter estimation of random signals have been employed to tease out trends from within the data. Analysis of physiological signals from sleeping infants has revealed hourly oscillations in their body temperatures that are highly correlated with their breathing rate and breathing rate interquartile range (variability). The oscillations appear to have the highest magnitude when the infant rectal temperatures are near to the mean rectal temperature value. Although some form of relationship between temperature and respiration is evident, insufficient information has been yielded by these signal processing techniques to divulge exactly what the relationship is.
A mathematical model of the human thermoregulatory control system has been developed to investigate the behaviour of temperature regulation in infants. The model has been used to test the hypothesis that infant thermal control is inherently unstable. In this model, heat flow through the body tissues is calculated and the effect of bedding on heat loss is also considered. Automatic temperature regulation is achieved by negative feedback control of the metabolic rate, sweat rate and blood flow distribution in the model. Under physiologically normal conditions, the model shows oscillatory behaviour with a period of approximately one hour. Therefore, the model indicates that the temperature oscillations that have been observed in infants in the home environment, may be a direct result of a marginally stable or unstable thermoregulatory control system. The oscillations occurred when the model was operating just below the thermoneutral point. If the mean infant rectal temperature is assumed to be close to the thermoneutral point, then the model behaviour agrees closely with the data collected from infants.
Evidence gathered from the behaviour of the thermoregulation model and from the signals collected from infants suggests that thermoregulation may be a dominant control system within the body, therefore, temperature may directly influence respiration. A mathematical model of the human infant respiratory control system has been developed to investigate the effect of body temperature on respiratory system behaviour during sleep and to test the hypothesis that the respiratory system is influenced directly by temperature and indirectly by thermoregulation. A multi-compartment model configuration is used to represent the carbon dioxide and oxygen stores within the body and a controller, sensitive to carbon dioxide and oxygen, adjusts the ventilation rate to complete a negative feedback control loop. Small changes in body temperatures were found to affect the steady state response of the respiratory model while the stability remained relatively unaffected. However, the respiratory model is highly sensitive to small amounts of noise added to blood flows, metabolic rate and arterial gas partial pressures. Therefore, the observed oscillations in infant breathing rate may be a direct effect of thermoregulation while the infant breathing rate interquartile range oscillations are probably induced by another mechanism.
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Murray, Sam. "Development of a soil respiration isotopic sampling system." Thesis, University of Canterbury. School of Biological Sciences, 2014. http://hdl.handle.net/10092/9652.
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The rate of carbon turnover in soil is a balance between the input of carbon by plants through their roots and associated fungi and the loss of carbon due to plant and microbial respiration, oxidation and leaching. Soil carbon dynamics are notoriously difficult to measure, and being able to separate total soil respiration into its autotrophic and heterotrophic components would help understanding of carbon cycling processes. Where autotrophic respiration originates from roots and their associated mycorrhizal fungi, using newly fixed carbon, and heterotrophic respiration originates from the breakdown of older soil organic matter.
By calculating the δ¹³C signature of respired CO₂ (the ratio of the abundances of C isotopes ¹²C and ¹³C) it is possible to determine whether it is of heterotrophic or autotrophic origin. In this study a 6 chamber, constant CO₂ concentration measuring apparatus was developed to determine both the rate of CO₂ efflux and to collect undisturbed CO₂ samples for isotope analysis. This apparatus was tested using live soil samples with different δ¹³C values (-22 ‰ to -27 ‰) and respiration rates (2 – 8 µmol m⁻² s⁻¹) obtained from various locations in New Zealand. Testing involved taking samples using the respiration apparatus, then incubating the same samples in a bag, and then comparing the two. There was no difference between the results from the soil respiration apparatus and the bags (R²=0.96, p=0.0002).
Twelve microcosms including soil and grass were extracted from a newly converted dairy farm and placed into in growth cabinets. Diurnal courses of partitioned soil respiration were made over 24 hours with constant soil temperature to eliminate temperatures effect on soil respiration. Half were then covered with 90% shade cloth for 12 days to test if a reduction in light (and therefore newly fixed carbon) would have any effect on soil respiration. There was a significant reduction in soil respiration, yet no detectable change in the δ¹³C of soil respired CO₂ under heavily shaded treatment. There was however there was a shift towards heterotrophic dominated respiration. This shows that while L. perenne is resilient to surrounding conditions it is susceptible to change if exposed to different conditions for prolonged periods of time. The use of this new technique in the field will allow improved understanding of factors effecting soil C efflux.
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Soodt, Thomas [Verfasser]. "Development of Protective Artificial Respiration Strategies / Thomas Soodt." Aachen : Shaker, 2013. http://d-nb.info/1050343158/34.
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Shariati, Parvin. "Nitrate respiration in Bacillus licheniformis and Bacillus subtilis." Thesis, Heriot-Watt University, 2004. http://hdl.handle.net/10399/350.
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Mason, Laura Laura. "Signal processing methods for non-invasive respiration monitoring." Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:68b60700-1cf5-4587-8896-4e18a70c5193.
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This thesis investigates the feasibility of using a set of non-invasive biomedical signals to monitor respiration. The signals of interest being the electrocardiogram (EGG), photoplethysmography (PPG) and impedance plethysmography (IP) signals. The work has two main aims; the first being to estimate breathing rates from the signals, the second being to detect apnoeas from the signals. The fusion of information from different signals is used throughout in developing algorithms that give more accurate respiratory information than that obtained using one signal alone. Respiratory waveforms are derived from the signals, and the accuracy of detecting individual breaths from the waveforms is assessed and compared objectively. Results from evaluations on two separate databases show there is no waveform that gives sufficient accuracy to consider using it alone. A novel fusion method is developed which uses measurements from all three signals. This fusion method is based on weighting the estimates from each signal, according to the innovation from a Kalman filter model, applied to each respiratory waveform separately. The fused estimates give a higher overall correlation with respect to the reference breathing rate values than any of the breathing estimates derived from a single waveform. The detection of both central and obstructive sleep apnoea from the signals is investigated. It is shown that the accuracy of detecting central apnoeas from the IP signal using a timedomain method, often used in practice, can be improved by combining it with information from the frequency-domain. When discriminating between obstructive sleep apnoeic and non-apnoeic data it is seen that combining features from two signals results in a superior classification accuracy than is possible by using features from just one signal. The proposed classification system using just one of these signals, the EGG, is shown to give a performance accuracy comparable to that found in the literature. In conclusion this thesis shows that by fusing information from a number of non-invasive biomedical signals, estimations of breathing rates can be found with correlation 0.8. This is superior to estimation using only the impedance pneumography signal (correlation 0.64) which is currently used to monitor respiration. The fusion approach could potentially be applied to improve other non-invasive physiological monitoring systems.
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Crisp, Andrew John. "Cardiac ventricular receptors and the control of respiration." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241355.
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Armstrong, Anna Frances. "Cold acclimation of leaf respiration in 'Arabidopsis thaliana'." Thesis, University of York, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428409.
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Nobes, Catherine Diane. "The control of respiration of isolated liver cells." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316770.
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Gui, Dan Y. (Dan Yi). "The role of respiration in supporting cell proliferation." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/115451.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, June 2017.Cataloged from PDF version of thesis. "May 2017." Page 163 blank. Vita.
Includes bibliographical references.
Compared to non-proliferating cells, proliferating cells such as cancer cells have additional metabolic requirements for generating biomass. However, despite these additional requirements the components of the mammalian metabolic network in both proliferating and non-proliferating cells are largely the same. Thus, in order to balance the competing anabolic and catabolic needs of a proliferating cell, the same metabolic networks components must take on distinct roles. Understanding how the various network components support proliferation may lead to improvements in cancer therapy. It has long been known that mitochondrial respiration is essential for proliferation. However, the precise metabolic role that is filled by respiration is not well defined. This thesis focuses on understanding the role of respiration in supporting mammalian proliferation. In non-proliferating cells respiration is considered to be primarily an ATP-producing catabolic process. We find that in proliferating cells, respiration serves a crucial anabolic role by providing access to an electron acceptor in the form of molecular oxygen. Electron acceptor availability is required for maintaining NAD+/NADH homeostasis and supporting aspartate synthesis. In conditions where alternative electron acceptors are provided such that cells can maintain NAD+/NADH homeostasis through alternative pathways, or when exogenous aspartate is provided, respiration is dispensable for proliferation. These findings highlight that metabolic dependencies can be modified by environmental conditions. Consistent with this, we find that altering NAD+/NADH homeostasis through alternative pathways or providing exogenous aspartate can modulate cellular sensitivity to respiration inhibitors such as metformin. Collectively, these studies contribute to an understanding of how metabolism supports biomass generation for proliferation and offers insight to how metabolism could be targeted for cancer therapy.
by Dan Y. Gui.
Ph. D.
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Yue, Shichao. "Extracting multi-person respiration from entangled RF signals." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/117817.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2018.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 53-56).
Recent advances in wireless systems have demonstrated the possibility of tracking a person's respiration using the RF signals that bounce off her body. The resulting breathing signal can be used to infer the person's sleep quality and stages; it also allows for monitoring sleep apnea and other sleep disordered breathing; all without any body contact. Unfortunately however past work fails when people are close to each other, e.g., a couple sharing the same bed. In this case, the breathing signals of nearby individuals interfere with each other and super-impose in the received signal. This thesis presents DeepSleep, the first RF-based respiration monitoring system that can recover the breathing signals of multiple individuals even when they are separated by zero distance. To design DeepSleep, we model interference due to multiple reflected RF signals and demonstrate that the original breathing can be recovered via independent component analysis. We design a full system that eliminates interference and recovers the original breathing signals. We empirically evaluate DeepSleep using 21 nights of sleep and over 150 hours of data from 13 couples who share the bed. Our results show that DeepSleep is very accurate. Specifically, the differences between the breathing signals it recovers and the ground truth are on par with the difference between the same breathing signal measured at the person's chest and belly. Thesis Supervisor: Dina Katabi
by Shichao Yue.
S.M.
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Jonsson, Joakim. "Detecting Cardiac Pulsatility and Respiration using Multiband fMRI." Thesis, Umeå universitet, Institutionen för fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149863.
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Purpose: Arterial stiffening poses an increased risk of cerebrovascular diseases, cognitive impairments, and even dementia as cardiac pulsations reach further into the brain causing white matter hyperintensities and microbleeds. Therefore it is of interest to obtain methods to estimate and map cardiac related pulsatility in the brain. Improvements of functional magnetic resonance imaging (fMRI) sequences is potentially allowing detection of rapid physiological processes in the echo-planar imaging (EPI) signal in the brainthrough a higher sampling rate. Specifically in this thesis, estimation and localization of cardiac pulsation and respiration is conducted through analysis of resting state data obtained with a multiband EPI sequence that permits whole brain imaging at a shorter repetition time (TR) than conventional EPI. The origin of these physiological signals are likely a mixture of inflow and compartment volume shifts during the cardiac- and respiratory cycles. As the amount of physiologically related signal in the multiband sequence used at the Biomedical Engineering Dept. R&D, Umeå University Hospital is unknown, the aim of this project is to find and map cardiac pulsatility and respiration for future research. Methods: Multiband fMRI data from 8 subjects was used, collected in a 3 Tesla scanner using a 32-channel head coil. The physiological signals were estimated through an algorithm that was developed to down-sample and temporally shift copies of simultaneous recordings of pulse and respiration. These signals were obtained using the scanner’s built-in pulse oximeter and a respiration belt. The shifted copies were voxel-wise, and slice by slice, correlated to the fMRI data using Pearson correlation. The time shift yielding maximum mean correlation within the brain was, for each slice, used to create statistical maps for significant voxels to show the localization and magnitude of correlation for cardiac pulsation andrespiration. Results: Many voxels around and nearby larger vessels and ventricles were highly correlated with the down-sampled, time shifted signals of the cardiac pulsation for all subjects. The cardiac pulsation maps resembled cerebral vasculature and were mostly localized around the Circle of Willis, brainstem, and the ventricles. Respiration signal was also highly correlated, and spatially located at the sides of the brain although mostly concentrated at the parietal- and occipital lobes. Conclusion: The results demonstrated that many voxels in the brain were highly correlated with cardiac pulsation and respiration using multiband EPI, and the statistical maps revealed distinct patterns for both of the physiological signals. This method and results for mapping cardiac related pulsatility, and respiration could be used for future research in order to better understand cerebral diseases and impairments, and alsoto improve fMRI filtering. Keywords: Arterial stiffness, Functional magnetic resonance imaging, Resting state, Multiband, CardiacPulsation, Respiration, Correlation analysisSyfte: Arteriell förstyvning medför en ökad risk för cerebrovaskulära sjukdomar, kognitiva störningar och till och med demens då hjärtpulsationer når längre in i hjärnan orsakar vit materia hyperintensiteter och mikroblödningar. Av detta skäl är det därför av intresse att ta fram metoder för att estimera och kartlägga hjärtrelaterad pulsationer i hjärnan. Förbättringar av funktionella magnetresonanstomografi (fMRI) sekvenser kan möjliggöra detektering av snabba fysiologiska processer i den eko-planära (EPI) signalen i hjärnan genom en högre samplingsfrekvens. Specifikt i denna uppsats, utförs en skattning och lokalisering av hjärtpulsation och respiration genom analys av ’resting state’ data erhållet av en multiband-EPI sekvens som tillåter bildgivning av hela hjärnan med en kortare repetitionstid (TR) än konventionell EPI. Ursprunget avdessa fysiologiska signaler är sannolikt från en blandning av flöde- och volymsförändringar under hjärt- och respirationscyklerna. Då mängden av fysiologiskt relaterad signaler i multiband sekvensen, som används på Biomedicinska avdelningen, FoU Umeå Universitetssjukhust, är okänd så är målet med projektet att hitta och kartlägga hjärtpulsation och respiration för framtida forskning. Metod: Multiband fMRI data från 8 personer användes, insamlade från en 3 Tesla scanner med en 32-kanals huvudspole. De fysiologiska signalerna uppskattades genom en algoritm som utveckades för att sampla ned och tidsförskjuta kopior av simultant tagna signaler av puls och respiration. Dessa signaler samlades in med skannerns inbyggda pulsoximeter och andningsband. De förskjutna kopiorna var voxelvis, snitt för snitt, korrelerade med fMRI datat med användning av Pearson-korrelation. Det tidsskift somför varje snitt resulterade i maximal medelkorrelation i hjärnan användes för att skapa statistiska kartor, med endast signifikanta voxlar, för att visa var och hur mycket korrelation av hjärtpulsation och respiration som finns. Resultat: Många voxlar runt och nära större kärl och ventriklar var för alla personer starkt korrelerade medde samtidigt tagna, och tidsförskjutna signalerna av hjärtpulsation. Pulsationskartorna liknade cerebral vaskulatur och var mestadels lokaliserade kring Willis ring, hjärnstammen och ventriklar. Respirationssignalen var även starkt korrelerad och lokaliserad på sidorna av hjärnan, mestadels koncentrerat vid parietal- och occipital loberna. Slutsats: Resultaten visade att många voxlar i hjärnan var starkt korrelerade med hjärtpulsation och respiration vid användning av multiband EPI, och de statistiska kartorna avslöjade distinkta mönster för de båda fysiologiska signalerna. Den framtagna metoden och dess resultat för kartläggning av hjärtrelaterade pulsationer och respiration kan användas i framtida forskning i syfte att bättre förstå cerebrala sjukdomar och nedsättning, även för att förbättre fMRI filtrering. Nyckelord: Arteriell förstyvning, Funktionell magnetresonanstomografi, Resting state, Multiband, Hjärtpulsation, Andning, Korrelationsanalys
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Nydahl, Anna. "Coastal microbial respiration in a climate change perspective." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-62734.
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In a climate change perspective increased precipitation and temperature are expected which should influence the coastal microbial food web. Precipitation will have a strong impact on river flow and thereby increase the carbon input to the coastal zone as well as lowering the marine salinity by dilution with freshwater. Simultaneously temperature may increase by 2-5 °C, potentially influencing e.g. metabolic processes. Consequences of this have been evaluated in this thesis with focus on microbial respiration in paper II and IV. A temperature increase of 3 °C will have a marked effect on microbial respiration rates in the coastal zone. The effect of temperature on microbial respiration showed a median Q10 value of 25 with markedly higher values during winter conditions (around 0°C). These Q10 values are several-fold higher than found in oceanic environments. The conclusion was in accordance with a consistent temperature limitation of microbial respiration during an annual field study, however, shifting to DOC limitation at the elevated temperature. Neither bacterial production nor phytoplankton production showed a consistent temperature effect, suggesting that the biomass production at the base of the food web is less sensitive to a temperature increase. Results from both a field study and a fully factorial microcosm experiment supported the conclusion. Our results suggested that areas dealing with hypoxia today will most likely expand in the future, due to increased respiration caused by higher temperatures and larger riverine output of dissolved organic carbon. Pelagic respiration measurements in the sea are relatively scarce in the literature, mainly due to the lack of sufficiently good and user friendly techniques. New methods such as the dynamic luminescence quenching technique for oxygen concentration have been developed. This makes it possible to obtain continuous measurements of oxygen in an enclosed vial. Two different commercially available systems based on the dynamic luminescence quenching technique were evaluated from the aspect of precision, accuracy and detection limit when applied to respiration measurements in natural pelagic samples. The Optode setup in paper III showed a practical detection limit of 0.30 mmol m-3 d-1, which can be applied to measure respiration in productive coastal waters (used in paper IV). This included development of a stopper where the sensor was attached, stringent temperature control, proper stirring and compensation for an observed system drift. For controlled laboratory experiments with organisms smaller than 1 µm the Sensor Dish Reader (paper I) has sufficient detection limit of (4.8 mmol m-3 d-1). This required a stringent temperature control and manual temperature correction. The Sensor Dish Reader gives the opportunity to perform multiple treatments at low cost (used in paper II), but the precision is too low for field studies due to the between ampule variation.Östersjön är ett brackvatten hav som sträcker sig från Bottenviken i norr till de danska sunden i söder och omsluts av en landmassa som representeras av nio länder. Denna miljö är på många sett unik genom stor sötvattenpåverkan och litet utbyte med världshaven (30 års omsättningstid). Östersjön utsätts framförallt för tillförsel av ämnen från såväl naturliga som antropogena aktiviteter. Något som ofta uppmärksammas är problem med syrefria områden och döda havsbottnar. Detta anses påverkas av både klimatförändringar och övergödning. En av de biologiska prosesser som påverkar syresituationen i haven är respiration, syreförbrukning, som utförs av de flesta levande organismerna i Östersjön. Den här avhandlingen presenterar resultat på hur bakteriers syreförbrukning påverkas av de förändringar vi förväntar oss i vårt klimat i framtiden. Det är framförallt ökad temperatur och ökat vattenflöde i våra floder som i sin tur leder till snabbare omsättning och tillförsel av näring åt bakteriesamhället. Resultaten från artiklarna II och IV visar att den potentiella temperaturökningen som väntas skulle öka syreförbrukningen i kustnära områden. Den blir extra stor i kustområden, troligen på grund av stor tillgång på organiskt material från älvarna. Även den högre tillförseln av näringsämnen kan ökan syreförbrukningen enligt artikel II. De områden som idag är syrefattiga kommer på grund av detta att expandera, framförallt längs kusterna där nya områden kan uppstå. Eventuellt kan det vara en förklaring till den ökande ytan av syrefria bottnar i i Östersjön och världshaven. För att kunna utföra mätningar av syreförbrukning krävs väldigt precisa och gärna användarvänliga metoder som lätt kan tillämpas i fält. I avhandlingen presenteras hur två olika mätmetoder optimeras för att göra tillförlitliga förbrukningsmätningar av syre. Ny teknik gör att syrehalten kan mätas med en ljusbaserad metod som skiljer sig från dagens kemiska bl.a. genom att resultaten kan följas löpande på en dator. De båda metoderna kräver en väldigt precis temperaturkontroll. Optod uppsättningen presenterad i artikel III innefattaer en volym på 1 liter och organismer upp till en storlek på 50 μm omfattas i den uppmäta syreföbrukningen. Denna metod rekommenderas fö fätmäningar, och anvädes föfätmäningar i Artikel IV. I utvecklingen ingick utformning av en kork fö att montera optod-sensorn i. I artikel I presenteras en utrustning som baseras påen mindre volym (5 ml) vilket innebä att endast mäningar påbakterier och organismer mindre ä 1 μm kan anses tillfölitliga. Detta i kombination med viss variation mellan mäflaskor gö att den framföallt rekomenderas fö anvädning i laboratoriemiljö Det systemet anvädes fö mäningarna av syreföbrukning i laboratorieexperimentet som presenteras i artikel II.