Heat induced protein haze is a common problem in white wine. Grape derived pathogenesis related proteins slowly denature and aggregate during wine storage and this gives rise to light dispersing haze. Protein haze formation is currently prevented by removing proteins using bentonite, an aluminium silicate clay, but this method has drawbacks. A potential alternative or complementary method is the use of haze protective factors ( HPF ), specific mannoproteins from Saccharomyces cerevisiae that visually reduce protein haze. Hpf1p was originally isolated from Muscat Gordo Blanco wine and Hpf2p from a synthetic grape juice ferment. Based on partial amino acid sequences, putative structural genes, HPF1 and HPF2, for these proteins were identified. HPF1 has a homologue, HPF1 ', ( 71 % similarity ) in S. cerevisiae. Sequence analysis suggests that Hpf1p, Hpf1 ' p and Hpf2p are localised to the cell wall or plasma membrane. This study aimed to determine the biological function of the HPF genes in S. cerevisiae. HPF overexpression and deletion strains were constructed and analysed for cell wall related phenotypes. Under a number of conditions, including cold temperature and ethanol stress, the hpf1 Δ hpf1 ' Δ strain was more tolerant than the wild type strain. However, mating efficiency of the hpf1 Δ hpf1 ' Δ strain was significantly less than the wild type strain and this was found to be correlated with the persistence of a septum between the mating partners. The decreased mating efficiency was also mating type specific, only occurring in MAT α cells. This study also aimed to establish conclusively that the HPF genes do indeed encode proteins with haze protective properties. Haze protective activity of the material from ferment supernatants was assessed. Material from the HPF deletion strains exhibited significantly less haze protective activity than the wild type. Moreover, material derived from HPF1 and HPF1 ' overexpressors was more active than material from the wild type. A 6xHis - tagged Hpf2p was expressed and purified using immobilised metal affinity chromatography. This Hpf2p had significant haze protective activity. Modification of N - glycans of 6xHis - Hpf2p by Endoglycosidase H decreased its haze protective activity.visually reduce protein haze. Hpf1p was originally isolated from Muscat Gordo Blanco wine and Hpf2p from a synthetic grape juice ferment. Based on partial amino acid sequences, putative structural genes, HPF1 and HPF2, for these proteins were identified. HPF1 has a homologue, HPF1 ', ( 71 % similarity ) in S. cerevisiae. Sequence analysis suggests that Hpf1p, Hpf1 ' p and Hpf2p are localised to the cell wall or plasma membrane. This study aimed to determine the biological function of the HPF genes in S. cerevisiae. HPF overexpression and deletion strains were constructed and analysed for cell wall related phenotypes. Under a number of conditions, including cold temperature and ethanol stress, the hpf1 Δ hpf1 ' Δ strain was more tolerant than the wild type strain. However, mating efficiency of the hpf1 Δ hpf1 ' Δ strain was significantly less than the wild type strain and this was found to be correlated with the persistence of a septum between the mating partners. The decreased mating efficiency was also mating type specific, only occurring in MAT α cells. This study also aimed to establish conclusively that the HPF genes do indeed encode proteins with haze protective properties. Haze protective activity of the material from ferment supernatants was assessed. Material from the HPF deletion strains exhibited significantly less haze protective activity than the wild type. Moreover, material derived from HPF1 and HPF1 ' overexpressors was more active than material from the wild type. A 6xHis - tagged Hpf2p was expressed and purified using immobilised metal affinity chromatography. This Hpf2p had significant haze protective activity. Modification of N - glycans of 6xHis - Hpf2p by Endoglycosidase H decreased its haze protective activity. / Thesis (Ph.D.)--School of Agriculture and Wine, 2003.

L'élimination des protéines est une étape clé lors de la production du vin blanc afin d'éviter l'apparition éventuelle d'un voile inoffensif mais inesthétique. Des solutions de rechange à l'utilisation de la bentonite sont activement recherchées en raison des problèmes technologiques, organoleptiques et de durabilité associés à son utilisation. Dans cette étude, MpAPr1, une protéase aspartique extracellulaire préalablement isolée et partiellement caractérisée à partir de la levure Metschnikowia pulcherrima, a été clonée et exprimée de manière hétérologue dans la levure Komagataella pastoris. Les propriétés enzymatiques de MpAPr1 ont été initialement caractérisées dans un extrait brut. Après plusieurs essais faisant appel à différentes techniques, MpAPr1 a été purifié avec succès par chromatographie échangeuse de cations. Son activité contre les protéines de raisin a été initialement testée dans une solution modèle dans des conditions environnementales optimales pour l'activité de MpAPr1 puis dans celles qui règnent lors de la vinification. Ensuite, l'activité de MpAPr1 a été évaluée dans du moût de raisin et au cours de la fermentation alcoolique. La présence de MpAPr1, supplémenté au moût de raisin, a entraîné une dégradation partielle des protéines de raisin tout au long de la fermentation et une légère différence dans la composition en composés volatils du vin. L'étude a confirmé que les protéases aspartiques pourraient représenter une alternative à la bentonite pour l'industrie du vin et que les levures non-Saccharomyces telles que M. pulcherrima pourraient avoir un impact bénéfique sur les propriétés du vin. / Protein removal is a key step during the production of white wine in order to avoid the possible appearance of a harmless but unsightly haze. Alternatives to the use of bentonite are actively sought because of technological, organoleptic and sustainability issues associated with its use. In this study, MpAPr1, an extracellular aspartic protease previously isolated and partially characterised from the yeast Metschnikowia pulcherrima, was cloned and expressed heterologously in Komagataella pastoris. Enzymatic properties of MpAPr1 were initially characterised in a crude extract. After several attempts using different techniques, MpAPr1 was successfully purified via cation exchange chromatography. Its activity against haze-forming grape proteins was initially tested in a model solution under optimal environmental conditions for MpAPr1 activity and under those occurring during winemaking. Thereafter, MpAPr1 activity was evaluated in grape must and throughout alcoholic fermentation. The presence of MpAPr1, supplemented to grape must, resulted in the partial degradation of grape proteins throughout fermentation and ultimately in a slight difference in the wine’s composition in volatile compounds. The study provides further evidence that aspartic proteases could represent a potential alternative to bentonite for the wine industry and that non-Saccharomyces yeasts such as M. pulcherrima could have a beneficial impact on wine properties.

Le réchauffement climatique dans l’Arctique canadien est deux fois plus rapide que la moyenne globale, ce qui accélère la fonte de la banquise et bouleverse radicalement la faune, la flore et les communautés de la région tout entière. Ce réchauffement est causé non seulement par la hausse des émissions de gaz à effet de serre, mais également par des agents de forçage climatique de courte durée comme les aérosols troposphériques. Toutefois, le forçage radiatif des aérosols dans la région polaire est beaucoup moins bien estimé que celui des gaz à effet de serre, notamment le CO2, et demeure toujours incertain. Cette grande incertitude résulte principalement de la grande variabilité spatiotemporelle des propriétés chimiques et physiques des aérosols, en plus de la complexité des boucles de rétroaction observées en Arctique. D’ailleurs, les données sur les caractéristiques des aérosols et de leur répartition à travers la région sont très limitées, et ce, plus particulièrement dans le Haut-Arctique canadien. Pour remédier à ce problème, une série de mesures a été effectuée sur une période de 3 ans (2016-2019) dans le laboratoire de recherche sur l’environnement atmosphérique polaire (PEARL, 80N 86O) situé près de la station météorologique d’Eureka, au Nunavut, Canada. La distribution en taille des aérosols a été mesurée en se servant de plusieurs instruments, dont un compteur optique de particules (OPC), un granulomètre de mobilité électrique à balayage (SMPS) et un granulomètre aérodynamique (APS). Les propriétés optiques des aérosols ont été déterminées avec deux extinctiomètres photoacoustiques (PAX) qui opèrent respectivement à des longueurs d’onde de 405 et 870 nm. Les observations réalisées à l’observatoire PEARL démontrent une forte variation saisonnière dans les propriétés optiques et microphysiques des aérosols polaires. Pendant l’hiver et le printemps, l’atmosphère arctique est envahie par une brume sèche d’origine anthropique qui se traduit par une forte augmentation dans la taille, la concentration en nombre et les propriétés optiques extensives des aérosols. Les épisodes de brume arctique commencent généralement en mi-décembre, où des évènements de poussières minérales ont aussi été observés, et se terminent en mai où la formation et le grossissement de nouvelles particules s’amorcent. Le début du printemps mesure les concentrations d’aérosol en mode accumulation les plus élevées durant l’année. Les aérosols les plus sombres qui composent la brume arctique ont été identifiés comme étant de la suie ou du carbone noir transporté dans l’Arctique à partir de l’Eurasie et de l’Alaska. Quelques relations systématiques entre les propriétés optiques et la distribution de taille des aérosols ont également été calculées et révèlent une différence majeure entre les aérosols interagissant avec la lumière à 405 et 870 nm. / Global warming in the Canadian Arctic is twice as fast as the global average, accelerating the melting of sea ice and radically disrupting the fauna, the flora, and the communities of the whole region. Arctic warming is caused not only by rising greenhouse gas emissions, but also by the short-lived climate forcing agents such as tropospheric aerosols. However, aerosol radiative forcing in the polar region is less precisely estimated than that of greenhouse gases, notably CO2, and remains highly uncertain. This large uncertainty arises mainly from the high spatiotemporal variability in aerosol chemical and physical properties, in addition to the complexity of the feedback loops observed in the Arctic. Furthermore, datasets on aerosol characteristics and their distribution across the region are very limited, particularly in the Canadian High Arctic. To address this issue, a series of measurements were conducted over a 3-year period (2016-2019) at the Polar Atmospheric Environment Research Laboratory (PEARL, 80N 86W) near Eureka weather station, in Nunavut, Canada. Aerosol size distribution was measured using several instruments including an Optical Particle Counter (OPC), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS). Aerosol optical properties were determined by two Photoacoustic Extinctiometers (PAXs) which operate at wavelengths of 405 nm and 870 nm, respectively. Observations made at the PEARL observatory show a strong seasonal variation in the optical and microphysical properties of polar aerosols. In the winter and spring, the Arctic atmosphere is impacted by an anthropogenic haze that results in a sharp increase in aerosol size, number concentration, and optical properties. Arctic haze episodes typically occur in mid-December, when mineral dust events have also been observed, and end in May when formation and growth of new particles begin. Early spring exhibits the highest accumulation-mode aerosol concentrations during the year. The darkest Arctic haze aerosols have been identified as soot or black carbon transported into the Arctic from Eurasia and Alaska. Some systematic relationships among aerosol optical properties and size distribution have also been calculated and reveal a major difference between aerosols interacting with light at 405 nm and 870 nm.

The IPCC's report in 2018 projects global warming will increase by 1.5oC in 2030, which makes contribution of each country to control their emissions becomes significant. This study seeks to investigate what entitlement human beings have over the absorptive capacity of the atmosphere as well as the harm it caused by elaborating the Entitlement Theory of Justice, thereto, finding out how the burden of climate change should be distributed according to the Polluter Pays Principle (PPP) and the Equal per Capita Shares Principle (ECSP). Furthermore, this study seeks to investigate Indonesia's part in increasing the burden of climate change and whether Indonesia should be held responsible for its part by comparing data of Indonesia's emissions to some developed countries' emissions. Humanity has a collective ownership over the absorptive capacity of the atmosphere, which implies that every individual has equal share of this absorptive capacity. A violation of this equal share should be compensated. The PPP suggests countries, who has the most cumulative amount of emissions from the past to present, to compensate and bear the climate change burden. While, the ECSP suggests countries, who emit more than their equal share per capita, to bear the climate change burden and reduce their emissions. Indonesia, despites massive amounts of CO2 released by its deforestation and annual haze, contributes insignificant to climate change due to both its cumulative and per capita emissions are considerably low compared to developed countries and even lower than acountry with large population size such as China.

This thesis introduces methods for adding user-guided depth-aware effects to images captured with a consumer-grade stereo camera with minimal user interaction. In particular, we present methods for highlighted depth-of-field, haze, depth-of-field, and image relighting. Unlike many prior methods for adding such effects, we do not assume prior scene models or require extensive user guidance to create such models, nor do we assume multiple input images. We also do not require specialized camera rigs or other equipment such as light-field camera arrays, active lighting, etc. Instead, we use only an easily portable and affordable consumer-grade stereo camera. The depth is calculated from a stereo image pair using an extended version of PatchMatch Stereo designed to compute not only image disparities but also normals for visible surfaces. We also introduce a pipeline for rendering multiple effects in the order they would occur physically. Each can be added, removed, or adjusted in the pipeline without having to reapply subsequent effects. Individually or in combination, these effects can be used to enhance the sense of depth or structure in images and provide increased artistic control. Our interface also allows editing the stereo pair together in a fashion that preserves stereo consistency, or the effects can be applied to a single image only, thus leveraging the advantages of stereo acquisition even to produce a single photograph.

An Airborne Mobile Aerosol Lidar (AMALi) was constructed and built at Alfred-Wegener-Institute for Polar and Marine Research (AWI) in Potsdam, Germany for the lower tropospheric aerosol and cloud research under tough arctic conditions. The system was successfully used during two AWI airborne field campaigns, ASTAR 2004 and SVALEX 2005, performed in vicinity of Spitsbergen in the Arctic. The novel evaluation schemes, the Two-Stream Inversion and the Iterative Airborne Inversion, were applied to the obtained lidar data. Thereby, calculation of the particle extinction and backscatter coefficient profiles with corresponding lidar ratio profiles characteristic for the arctic air was possible. The comparison of these lidar results with the results of other in-situ and remote instrumentation (ground based Koldewey Aerosol Raman Lidar (KARL), sunphotometer, radiosounding, satellite imagery) allowed to provided clean contra polluted (Arctic Haze) characteristics of the arctic aerosols. Moreover, the data interpretation by means of the ECMWF Operational Analyses and small-scale dispersion model EULAG allowed studying the effects of the Spitsbergens orography on the aerosol load in the Planetary Boundary Layer. With respect to the cloud studies a new methodology of alternated remote AMALi measurements with the airborne in-situ cloud optical and microphysical parameters measurements was proved feasible for the low density mixed-phase cloud studies. An example of such approach during observation of the natural cloud seeding (feeder-seeder phenomenon) with ice crystals precipitating into the lower supercooled stratocumulus deck were discussed in terms of the lidar signal intensity profiles and corresponding depolarisation ratio profiles. For parts of the cloud system characterised by almost negligible multiple scattering the calculation of the particle backscatter coefficient profiles was possible using the lidar ratio information obtained from the in-situ measurements in ice-crystal cloud and water cloud. / Das Airborne Mobile Aerosol Lidar (AMALi) wurde am Alfred-Wegener-Institut für Polar- und Meeresforschung in Potsdam für die Untersuchung arktischer Aerosole und Wolken der unteren Troposphäre entwickelt und gebaut. Das AMALi wurde erfolgreich in zwei AWI Flugzeugmesskampagnen, der ASTAR 2004 und der SvalEx 2005, die in Spitzbergen in der Arktis durchgeführt wurden, eingesetzt. Zwei neue Lidar Datenauswertungsmethoden wurden implementiert: die Two-Stream Inversion und die Iterative Airborne Inversion. Damit erwies sich die Berechnung der Profile der Teilchen Rückstreu- und Extinktionskoeffizienten mit einem entsprechenden Lidar Verhältnis, das charakteristisch für arktische Luft ist, als möglich. Der Vergleich dieser Auswertungen mit den Resultaten, die mit verschiedenen Fernerkundungs- und In-situ Instrumenten gewonnen worden waren (stationäres Koldewey Aerosol Raman Lidar KARL, Sonnenphotometer, Radiosondierung und Satellitenbilder) ermöglichten die Interpretation der Lidar-Resultate und eine Charakterisierung sowohl der reinen als auch der verschmutzten Luft. Außerdem konnten die Lidardaten mit operationellen ECMWF Daten und dem kleinskaligen Dispersionsmodel EULAG verglichen werden. Dadurch konnte der Einfluss der Spitzbergener Orographie auf die Aerosolladung der Planetaren Grenzschicht untersucht werden. Für Wolkenmessungen wurde eine neue Methode der alternativen Fernerkundung mit dem AMALi und flugzeuggetragenen In-situ Messgeräten verwendet, um optische und mikrophysikalische Eigenschaften der Wolken zu bestimmen. Diese Methode wurde erfolgreich implementiert und auf Mixed-Phase Wolken geringer optischen Dicke angewendet. Ein Beispiel hier stellt das Besamen der Wolken (sogenannte Feeder-Seeder Effekt) dar, bei dem Eiskristalle in eine niedrige unterkühlte Stratokumulus fallen. Dabei konnten Lidarsignale, Intensitätsprofile und die Volumendepolarisation gemessen werden. Zusätzlich konnten in den weniger dichten Bereichen der Wolken, in denen Vielfachstreuung vernachlässigbar ist, auch Profile des Teilchen Rückstreukoeffizienten berechnet werden, wobei Lidarverhältnisse genommen wurden, die aus In-situ Messungen für Wasser- und Eiswolken ermittelt wurden.

This study analyzes the available radar evidence in order to describe the morphology of channel networks around the north polar seas of Titan. Critical flow depths necessary to entrain water-ice grains, and denudation rates for a north polar channel network are discussed. The results indicate that channel networks on Titan have similar morphologies to channel networks cut by water on Earth. We also find that water-ice sediment should be readily entrained in the headwaters and downstream sections of the analyzed Titanian basin, given sufficient flow depths of liquid hydrocarbons. Also, the importance of slope and the elevated topography of the highlands surrounding the polar lakes are considered, as well as potential formation theories for the elevated highlands and low-lying maria that dominate the north polar region.

The Masters thesis deals with dependence of quality parameters of malt on the temperature of mashing at sweet wort preparation. The theoretical part focuses on the technology of malt production including description of ingredients, production parts, some kinds of malt and the quality parameters. There is also described the technology of sweet wort preparation and the methods of determination of the malt quality parameters in the sweet wort there. The experimental part focuses on determination of malt extract, viscosity, haze, colour, time of starch cleavage, pH, degree of fermentation and beta-glucans content. Based on temperature dependence of parameters, the individual samples were compared and the effects of temperature were discussed. The biggest extract of light and caramel malts was explored at 70 °C, of coloured malt at 50 °C. The lowest viscosity of light and coloured malts was explored at 65 °C, of caramel malt at 50 °C. The lowest haze of wort was at 65 °C. Ideal colour of all malts was at all mashing temperatures. Ideal pH of all malts was explored at 70 °C. Ideal time of starch cleavage was explored at 70-85 °C. The biggest achievable degree of fermentation and the hugest increase of beta-glucans content were explored at 65 °C.

No description available.

Nearly four decades of the Association of Southeast Asian Nations (ASEAN)-European Union (EU) relationship have witnessed the importance of ideas and identity alongside the economic interests in shaping the behaviour of the two sides. The study takes interest in understanding the EU’s actorness and the EU as a normative actor with and within Southeast Asia through a reflectivist lens. The thesis is an attempt to provide a new perspective on a relationship commonly assessed from an economic angle. It outlines the opportunity of non-traditional security (NTS) challenges to enhance EU actorness and normative influence in Southeast Asia. Against this backdrop, the study explores the dialogue and cooperative initiatives of two regions, which attach relatively little salience to each other. The study employs a NTS lens and draws upon the case of the Asian Financial Crisis of 1997-98, the haze in relation to forest governance, the Bali bombings of 2002 and the political conflict in Aceh. The study assumes that these NTS issues can stimulate processes of threat convergence as well as threat ‘othering’. It argues that these processes enhance European engagement in Southeast Asia and contribute to shaping regional stability in Southeast Asia. Furthermore, NTS crises present situations, where norms can become unstable, contested and substituted. This allows us to better examine the EU as a normative actor. To establish an understanding of the EU’s actorness and the EU as a normative actor, the empirical evidence will focus on the threat perceptions, motivations of action and activities of the EU and its member states. For the purpose of differentiating the EU as a normative actor, the study will also include the discussion of the normative objectives and behaviours of the EU and its member states and apply a reflectivist theoretical framework. Hypothetically, NTS crises trigger external assistance and normative influence and thus, they offer an opportunity to establish a more nuanced picture of the EU in the region. At the same time, the study acknowledges that there are a variety of constraints and variables that complicate the EU’s actorness. The thesis seeks to identify and discuss these. So far, scholarly publications have failed to apply the NTS perspective systematically. This thesis provides the first monograph-length treatment of the EU in Southeast Asia through a NTS and reflectivist lens.