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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Distribuição do EGF, EGFr, TGF-'beta'1, IL-1'alfa' e CSF-1 no periodonto de incisivos inferiores de ratos, em condições funcionais normal e alterada : estudo imunohistoquimico / Distribution of EGF, EGFr, TGF-'beta'1, IL-1'alfa' and CSF-1 in the periodontum of rat lower incisors, in normal and altered functional conditions

Pasetto, Silvana 25 February 2005 (has links)
Orientador: Pedro Duarte Novaes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-04T04:08:53Z (GMT). No. of bitstreams: 1 Pasetto_Silvana_D.pdf: 2934024 bytes, checksum: e55fbc0178e149fd28ba97d8ca9267d2 (MD5) Previous issue date: 2005 / Resumo: O objetivo deste estudo, foi analisar, por meio da técnica de imunohistoquímica, a distribuição do EGF, EGFr, TGF-b1, IL-1a e CSF-1, em 3 diferentes regiões dos incisivos inferiores de ratos, em condições funcionais normais e alteradas. Cinquenta animais, tiveram seus incisivos inferiores esquerdos, seccionados na altura da papila interdental, permanecendo fora de oclusão, sendo considerados hipofuncionais (Ho), seus contralaterais, em sobrecarga de função foram chamados hiperfuncionais (Hr). Vinte e cinco destes animais, sofreram a intervenção apenas uma única vez, sendo sacrificados 8 horas após, os outros vinte e cinco animais, sofreram a intervenção a cada 2 dias, sendo sacrificados no 8o dia de desoclusão. Dez animais pertencentes ao grupo controle (c), tiveram seus incisivos mantidos em condições funcionais normais de erupção. As hemimandíbulas de todos os animais foram fixadas em Karnovsky (com 0,1% de glutaraldeído), descalcificadas em EDTA 4,13%, subdivididas transversalmente em 5 regiões e incluídas em paraplast. Cortes transversais, com 4 mm de espessura de cada peça foram coletados em lâminas silanizadas e submetidos à técnica de imunohistoquímica. O folículo dental e o ligamento periodontal, mostraram variações nas intensidades de marcação, com todos os anticorpos, entre as diferentes regiões e entre os grupos analisados. Aparentemente, no entanto, os tecidos periodontais dos incisivos, após 8 dias de hipofunção, mostraram imunoreatividade mais forte, particularmente com o CSF-1, quando comparados com os incisivos, em condições funcionais normal e alterada. Os resultados parecem sugerir, que a ¿cascata¿ formada por essas moléculas, pode estar relacionada com a ampliação da via eruptiva do incisivo, que cresce por um período prolongado da vida do animal / Abstract: The aim of this study, was to analized, using immunohistochemical technique, the distribution of EGF, EGFr, TGF-b1, IL-1a e CSF-1, in periodontal tissues of three regions of rat lower incisors, in normal and altered functional conditions. Fifty animals, had their left lower incisors, cut at the level of the interdental papilla. Becoming out occlusion, they are considered hipofunctional teeth. The contralateral incisors, attrited with both upper incisors are considered hiperfunctional teeth. Twenty-five of these animals were killed 8 hours after. In the order twenty-five animals, the shortening was repeated every second day, and killed 8 days after. Ten animals were kept in normal functional conditions. The hemimandibules of all animals were fixed in Karnovsky (with 0,1% of glutaraldehyde), demineralized with EDTA, subdivided in five transversal regions and embedded in paraplast. Cross sections, 4 mm-thick were collected in glass slides coated with silane. The antibodies were developed with DAB plus H2O2. The dental follicle and the periodontal ligament showed variation in the staining intensities, for all antibodies used, among the different regions and groups analyzed. Apparently, however, the periodontal tissues of the incisors, after eight days of hipofunction, showed stronger immunoreactivity, particularly with CSF-1, as compared with incisors under normal and hiperfunctional conditions. The results suggest that this molecular ¿cascade¿, may be related with the enlargement of the rodent incisor eruptive pathway, since these teeth grow for a long period of animal¿s life / Doutorado / Histologia e Embriologia / Doutor em Biologia Buco-Dental
92

Characterisation of tight junctions in polymorphic light eruption

Pond, Emma January 2016 (has links)
Polymorphic light eruption (PLE) is the most common photodermatosis, affecting ~17% of the population. PLE is a delayed-type hypersensitivity response to an antigen induced by solar ultra-violet radiation (UVR). Its effects vary between patients, but the main symptom is a non-scarring, red papular rash in areas exposed to UVR. An effective therapy is low dose ultra-violet B (NBUVB) phototherapy. It is thought that NBUVB phototherapy desensitises the skin to further UVR exposure, but the mechanism by which this happens is unknown. Current immune based studies have been unable to clarify a mechanism as to how PLE arises. However, research in other skin diseases, such as psoriasis and atopic dermatitis, has shown that the barrier function of the skin is compromised by these disorders. Furthermore, research in lesional PLE skin showed an increase in barrier permeability of the skin. Recent research has specifically linked claudin proteins of tight junctions to the barrier dysfunction. Therefore, this study used quantitative immunofluorescent staining to measure tight junction (TJ) proteins and other barrier proteins of interest. Barrier function was also measured by transepidermal water loss (TEWL); a tracer dye penetration assay was used to measure TJ barrier function specifically. All measurements were made in non-lesional PLE skin, as compared to skin from healthy human volunteers. In photoprotected PLE skin the TJ protein claudin-1 was significantly reduced compared to healthy skin. The use of a tracer dye highlighted there was a reduction in TJ barrier function in PLE skin compared to healthy individuals. PLE and healthy skin were then exposed to ultra-violet B (UVB) and 24h later TJ proteins and TJ barrier function were measured. There was no change to claudin-1 after UVB exposure in PLE skin, but claudin-7 was reduced and claudin-12 increased. In contrast, in UVB-irradiated skin in normal controls after UVB exposure claudin-7 and claudin-12 were both increased, whilst claudin-1 was reduced. In PLE patients there was no further change to TJ barrier function, however, in normal controls, skin TJ barrier function was reduced post UVB. Both in healthy and PLE skin TEWL was unchanged before and after UVB exposure. Lastly TJ proteins were investigated after NBUVB in PLE patients. There was a further reduction in claudin-1 in PLE patients as well as a reduction in the TJ protein occludin, however the stratum corneum was significantly thickened. It could be suggested that this is a compensatory measure for the reduction seen in TJ barrier proteins, however further studies are needed to understand this. These data show significant differences in the TJ skin barrier in patients with PLE as compared to healthy human volunteers before and after UVB exposure. Furthermore, in PLE skin there is a significant change to the epidermis after NBUVB phototherapy. These data demonstrate that TJ protein expression and function is altered in PLE skin and may contribute to aetiology of the disorder, however the role of TJ barrier in aetiology is yet to be firmly established.
93

Lava Flow Hazard Assessment for the Idaho National Laboratory, Idaho Falls, and Pocatello, Idaho, U.S.A.

Gallant, Elisabeth 24 October 2016 (has links)
This study presents a probabilistic lava flow hazard assessment for the Idaho National Laboratory (INL) and the cities of Idaho Falls and Pocatello, Idaho. The impetus of this work is to estimate the conditional probability that a lava flow on the eastern Snake River Plain (ESRP) will impact the areas of interest given the formation of a new volcanic vent in the region. A list of 288 eruptive events, derived from a previously published inventory of 506 surface and 32 buried vents, was created to reduce the biasing of spatial density maps towards eruptions with multiple dependent vents. Conditional probabilities of new vents and events occurring on the ESRP were modeled using the the Sum of Asymptotic Mean Squared Error (SAMSE) optimal pilot bandwidth estimator with a bivariate Gaussian kernel function. Monte Carlo analyses of potential eruption scenarios were performed using MOLASSES, a cellular automata fluid flow simulator. Results show that Idaho Falls is impacted <1% of the time for both the vent and event simulations; Pocatello is not impacted by any simulated flows. 25.45% of vent flows and 33.74% of event flows breach the boundaries of INL. 18.27%of vent and 25.85% of event simulations initiate on the INL property. Annual inundation probabilities of 1.06 x 10-4 for vent-based flows and 7.12 x 10-5 for event-based flows are reported for INL; annual probabilities of an eruptive center initiating on INL property are 7.60 x 10-5 for vents and 5.45 x 10-5 for events. All of these values exceed the International Atomic Energy Agency’s acceptable risk probability of 10-7 by several orders of magnitude.
94

Quantifying the Timing and Controls of Magmatic Processes Associated with Volcanic Eruptions

January 2020 (has links)
abstract: Volcanic eruptions can be serious geologic hazards, and have the potential to effect human life, infrastructure, and climate. Therefore, an understanding of the evolution and conditions of the magmas stored beneath volcanoes prior to their eruption is crucial for the ability to monitor such systems and develop effective hazard mitigation plans. This dissertation combines classic petrologic tools such as mineral chemistry and thermometry with novel techniques such as diffusion chronometry and statistical modeling in order to better understand the processes and timing associated with volcanic eruptions. By examining zoned crystals from the fallout ash of Yellowstone’s most recent supereruption, my work shows that the rejuvenation of magma has the ability to trigger a catastrophic supereruption at Yellowstone caldera in the years (decades at most) prior to eruption. This provides one of the first studies to thoroughly identify a specific eruption trigger of a past eruption using the crystal record. Additionally, through experimental investigation, I created a novel diffusion chronometer with application to determine magmatic timescales in silicic volcanic systems (i.e., rhyolite/dacite). My results show that Mg-in-sanidine diffusion operates simultaneously by both a fast and slow diffusion path suggesting that experimentally-derived diffusion chronometers may be more complex than previously thought. When applying Mg-in-sanidine chronometry to zoned sanidine from the same supereruption at Yellowstone, the timing between rejuvenation and eruption is further resolved to as short as five months, providing a greater understanding of the timing of supereruption triggers. Additionally, I developed a new statistical model to examine the controls on a single volcano’s distribution of eruptions through time, therefore the controls on the timing between successive eruptions, or repose time. When examining six Cascade volcanoes with variable distribution patterns through time, my model shows these distributions are not result of sampling bias, rather may represent geologic processes. There is a robust negative correlation between average repose time and average magma composition (i.e., SiO2), suggesting this may be a controlling factor of long-term repose time at Cascade volcanoes. Together, my work provides a better vision for forecasting models to mitigate potential destruction. / Dissertation/Thesis / Doctoral Dissertation Geological Sciences 2020
95

Rekonstrukce vulkanických procesů komárovského komplexu na příkladu zaječovského centra / Reconstruction of volcanic processes in the Komárov Complex: case from the Zaječov volcanic centre

Machalová, Jitka January 2010 (has links)
Reconstruction of volcanic processes in the Komárov Complex: case from the Zaječov volcanic centre Summary Sheet lava flows with pillow breccias and hyaloclastites are interbedded agglomerate and volcaniclastics. This is the basic interpretation of rocks exposed in quarry near the town Zaječov. Rocks are part of geological area called Barrandien. Resediment volcaniclastic particles were transfer by sediment gravity flows. Agglomerates were deposited from volcaniclastic debris flow and fine grain volcanoclastics sediments from turbidity currents or hyperconcentrated flows. These types of flows named as eruption-fed aqueous density current are directly initiated by subaqueous volcanic eruption. One volcaniclastics strata set on the south wall of quarry was formed from subaquatic eruption plume, called steam copula. Steam copula created under the eruptive vent is water exclusion zone. Accretion lapilli can be formed in this zone if the copula is stable for a longer time. Accretion lapilli were generally considered to be able to form only in subaerial conditions, during the phreatomagmatic eruption till lately. Rocks exposed in quarry were probably formed during the Surtseyan eruption in shallow subaqueous setting. According to thin section lava flows are containing pseudomorphosis phenocrysts of olivine and...
96

Links Between Eruptive Styles, Magmatic Evolution, and Morphology of Low-Shield Volcanoes: Snake River Plain, Idaho

Barton, Katelyn J. 10 July 2020 (has links)
In this study, connections between chemical composition, eruption style, and topographic features of two shield volcanoes on the Snake River Plain, Idaho are examined. These relationships may then be applied to understanding silicate volcanic features throughout the inner solar system. Despite their similar ages and geographic locations, two young basaltic shield volcanoes—Kimama Butte (87 Ka) and Rocky Butte (95 Ka)—have strikingly different topographic profiles. The Kimama Butte shield has a diameter of 9 km and a height of 210 m. In contrast, Rocky Butte has a broad 36 km topographic shield that rises 140 m with less than 1° slopes. The vent crater at Rocky Butte developed as a large lava blister inflated and then collapsed forming a crater in which a lava lake developed. Little spatter accumulated throughout the eruption. In contrast, high spatter mounds and spatter-fed flows flank the main summit crater at Kimama Butte. Major- and trace-element compositions of the basaltic lavas are similar at the two shields, but distinct in Ni and Al2O3. The lavas range in TiO2 concentrations from 2.6–4.5 wt.% for Kimama Butte and 2.6–4.3 wt.% for Rocky Butte. These ranges can be related to magma evolution by fractional crystallization involving plagioclase and olivine without clinopyroxene. Compositions of the pre-eruptive phenocrysts are also similar at both shields but show variation with evolution. Olivine cores in the more primitive lavas are more Mg-rich (Fo80-72) than those in the evolved rocks (Fo65-55). Plagioclase cores are similarly more calcic in the more primitive flows (An78-68) than in the evolved ones (An65-52). Like other olivine-tholeiites on the Snake River Plain, the fO2 and fH2O were probably low with fO2 at -2△QFM and 0.1 wt.% H2O. Pressure of crystallization estimated from MELTS models is less than 3 kbar (~10 km deep). Calculated temperatures and magma viscosities overlap at both Kimama Butte (1226 to1147°C and 158 to14 Pa·s) and Rocky Butte (1251 to 1145°C and 75 to 8 Pa·s). However, Kimama Butte magma viscosities extend ~80 Pa·s higher than those for Rocky Butte lavas. The higher magma viscosities are the result of higher phenocryst proportions in spatter and spatter-fed lavas concentrated near the vent. Because lava temperature, volatile content, and chemical composition overlap at the two volcanoes, they are probably not important controls of shield-volcano morphology. This suggests that steep-capped shields are not created as a simple function of having more silicic lavas. Melt viscosities are also similar, but Rocky Butte lacks the phenocryst-rich (>30 vol %), higher magma viscosity lavas and the high spatter ramparts that form the cap at Kimama Butte. Thus, we conclude that eruption style and phenocryst content play the most important role in developing a low-shield volcano summit. Where eruptions shifted from lava lake overflow and tube development to late fountaining with short spatter-fed phenocryst-rich flows, steeper, higher shields develop.
97

Contribuer à la prévention des risques d'origine géologique :l'évaluation de la vulnérabilité des populations dans un contexte de rareté de données. Les cas de Goma et Bukavu (RDCongo)

Michellier, Caroline 13 September 2017 (has links) (PDF)
En République Démocratique du Congo (RDC), les provinces densément peuplées du Nord et du Sud-Kivu sont exposées à plusieurs types d’aléas d’origine géologique, tels que les glissements de terrain et les éruptions volcaniques des volcans Nyiragongo et Nyamulagira. En outre, la région souffre d'un faible niveau économique et de conflits récurrents qui contribuent à affaiblir encore davantage la population menacée.Cette recherche doctorale a été réalisée dans le cadre du projet GeoRisCA (Belspo, programme SSD, SD/RI/02A ;http://georisca.africamuseum.be), dont l'objectif global répond à la nécessité d'étudier les risques d’origine géologique dans la région du lac Kivu, afin de contribuer à la prévention des risques, à l’échelle régionale et locale. Cette recherche tente spécifiquement de répondre à la question de l’évaluation de la vulnérabilité d'une population confrontée à des aléas d’origine géologique, dans un contexte de rareté de données.L'étude a été menée dans deux sites urbains :Bukavu, chef-lieu de la province du Sud-Kivu qui compte environ 870.000 habitants, une ville affectée par des mouvements de terrain fréquents, et Goma, chef-lieu de la province du Nord-Kivu où vivent environ 775.000 personnes sous la menace des coulées de lave du volcan Nyiragongo dont la dernière éruption date de 2002. Pour combler le manque de données socio-démographiques fiables, une méthodologie adaptée à ce contexte particulier et s'appuyant sur la télédétection combinée à des enquêtes quantitatives, des entretiens approfondis et une connaissance détaillée de la zone étudiée a été développée. Deux bases de données démographiques comprenant des variables individuelles et de ménages ont été construites - une pour chaque ville étudiée. Ces données ont constitué la base de la réalisation de cartes détaillées de densité de population et ont permis l’analyse spatiale des caractéristiques socio-économiques des deux zones urbaines. Un indice de vulnérabilité sociale a ensuite été élaboré à partir de l’analyse en composantes principales (ACP) d’un large éventail de ces données socio-économiques. Un indice de vulnérabilité dit « opérationnel » a ensuite été déduit de l’indice de vulnérabilité sociale, afin de refléter davantage le contexte local et faciliter la reproductibilité du travail de terrain. La dernière étape de notre étude consistait à combiner spatialement l’évaluation de la vulnérabilité et la densité de la population aux analyses de susceptibilité aux glissements de terrain et de probabilité d’invasion des coulées de lave développées par des experts dans le cadre du projet GeoRisCA. Les cartes de risques obtenues constituent de nouveaux outils d'aide à la décision ;elles ont été transmises aux autorités locales et permettent d’une part le renforcement des politiques de réduction des risques de catastrophes et des programmes de prévention des catastrophes, et d’autre part une nouvelle approche de l’aménagement du territoire. Enfin, il est important de souligner que cette recherche n’aurait pu être réalisée sans un étroit partenariat avec les institutions scientifiques et les autorités locales, et a significativement contribué à améliorer les interactions entre ces différentes parties prenantes. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
98

Zu den Niederschlags- und Abflussverhältnissen in Europa im Jahr 1816, dem 'Jahr ohne Sommer

Börngen, Michael, Tetzlaff, Gerd, Mudelsee, Manfred 04 January 2017 (has links)
Das Jahr 1816 ist in die Klimatologie als das 'Jahr ohne Sommer' eingegangen. Der 1815 erfolgte Ausbruch des Vulkans Tambora auf der indonesischen Insel Sumbawa führte im darauffolgenden Jahr in vielen Teilen der Welt zu katastrophalen Missernten. Während in Nordamerika daran besonders die außerordentlich tiefen Sommertemperaturen Schuld waren, scheinen in Europa dafür sowohl die unter dem Durchschnitt liegenden Temperaturen wie auch die überdurchschnittlichen Regenmengen verantwortlich zu sein. Zeitgenössische Berichte wie auch Niederschlags- und Pegelaufzeichnungen aus verschiedenen Teilen Europas belegen eine besonders hohe Niederschlagstätigkeit im 'Erntemonat' Juli des Jahres 1816 und eine hohe Wasserführung der großen europäischen Ströme in den Jahren 1816 und 1817. / The year 1816 is known in climatology as the 'Year without Summer'. The eruption of the Tambora volcano on the Indonesian island Sumbawa in 1815 led to catastrophic crop failures over many parts of the world in the following year. Whereas in North America those failures originated from extraordinarily low summer temperatures, causes in Europe seem to have been below-normal temperatures as well as above-normal rainfall. Contemporary reports and also precipitation and river gauge measurements from different parts of Europe document enhanced precipitation in July 1816 ('Erntemonat') and high discharges of large European rivers in years 1816 and 1817.
99

Forecasting Volcanic Activity Using An Event Tree Analysis System And Logistic Regression

Junek, William N 01 January 2012 (has links)
Forecasts of short term volcanic activity are generated using an event tree process that is driven by a set of empirical statistical models derived through logistic regression. Each of the logistic models are constructed from a sparse and geographically diverse dataset that was assembled from a collection of historic volcanic unrest episodes. The dataset consists of monitoring measurements (e.g. seismic), source modeling results, and historic eruption information. Incorporating this data into a single set of models provides a simple mechanism for simultaneously accounting for the geophysical changes occurring within the volcano and the historic behavior of analog volcanoes. A bootstrapping analysis of the training dataset allowed for the estimation of robust logistic model coefficients. Probabilities generated from the logistic models increase with positive modeling results, escalating seismicity, and high eruption frequency. The cross validation process produced a series of receiver operating characteristic (ROC) curves with areas ranging between 0.78 - 0.81, which indicate the algorithm has good predictive capabilities. In addition, ROC curves also allowed for the determination of a false positive rate and optimum detection threshold for each stage of the algorithm. The results demonstrate the logistic models are highly transportable and can compete with, and in some cases outperform, non-transportable empirical models trained with site specific information. The incorporation of source modeling results into the event tree’s decision making process has begun the transition of volcano monitoring applications from simple mechanized pattern recognition algorithms to a physical model based forecasting system.
100

Impact of volcanic aerosols on clouds in cloud-system-resolving simulations and satellite observations

Haghighatnasab, Mahnoosh 12 July 2024 (has links)
Increased anthropogenic aerosols result in an enhancement in cloud droplet number concentration (Nd), which consequently modifies cloud and precipitation processes. It is unclear how exactly cloud liquid water path (LWP) and cloud fraction respond to aerosol perturbations. A volcanic eruption may help to better understand and quantify the cloud response to external perturbations, with a focus on short-term cloud adjustments. The goal of the present study is to understand and quantify the response of clouds to a se- lected volcanic eruption and to thereby advance the fundamental understanding of the cloud response to external forcing. In this study we used the ICON (ICOsahedral Non-hydrostatic) model in its numerical weather prediction setup at a cloud-system-resolving resolution of 2.5 km horizontally, to simulate the region around the Holuhraun volcano for one week (1 – 7 September 2014). The ICON-NWP version employed in this study does not include an interactive aerosol model. Therefore a new method for cloud condensation nuclei (CCN) activation in a mi- crophysics scheme that was developed specifically for this study is introduced. The CCN values were determined by interpolating from look-up tables and considering the corresponding pressure (p) and vertical velocity (w) values within each grid-box of the atmospheric model. Moreover, in order to improve the comparison between cloud microphysical variables and satellite retrievals, the MODIS simulator from the COSP (CFMIP Observation Simulator Package) framework was implemented into the source code of ICON-NWP. A pair of simulations, with and without the volcanic aerosol plume, allowed us to as- sess the simulated effective radiative forcing and its mechanisms, as well as its impact on adjustments of LWP and cloud fraction to the perturbations of Nd. In comparison to MODIS (Moderate Resolution Imaging Spectroradiometer) satellite retrievals, a clear enhancement of Nd due to the volcanic aerosol is detected and attributed. In contrast, no changes in either LWP or cloud fraction could be attributed. The on average almost unchanged LWP is a result of some LWP enhancement for thick and a decrease for thin clouds. In addition for this case of eruption, further experiments to examine how aerosols from the Holuhraun volcanic eruption affected LWP in regional simulations were conducted. The experiments aimed at: I) Determining the influence of different horizontal resolutions in ICON-NWP on LWP sensitivity. II) Assessing the sensitivity of LWP to changes in the autoconversion rate within the models. III) Comparing the responses of LWP and total column cloud droplet number concentration to the Holuhraun volcano eruption using different atmospheric models. The analysis indicates that increasing the horizontal resolution leads to higher LWP values in the model. However, the difference is not particularly significant, and the overall signal remains consistent in the volcano and no-volcano simulations across the three different resolutions. When the auto-conversion rate is increased by 10 times, there is a general reduction in LWP compared to the default rate. In addition, even relatively shallow clouds are sensitive to aerosol perturbations. Therefore, a larger number of clouds are affected by the volcanic plume in this scenario compared to the default auto-conversion case. When the auto-conversion rate is decreased by a factor of 10, there is a rise in LWP compared to the default rate. Our finding suggests that thicker clouds are more sensitive to aerosol perturbations in this case Comparative analysis of simulation results using different atmospheric models (ICON NWP, ICON-ART, and MetOffice Unified Model) for the Holuhraun volcano demonstrated consistent enhancements in total column Nd and LWP within the plume region compared to the no-volcano simulations. However, the magnitudes of the enhancements varied significantly between the different models. In order to examine the impact of these aerosols on a cloud regime different from the Holuhraun case, the Kilauea eruption and La Soufrière eruption, which occurred in low latitudes were examined with the same methodology. Our analyses revealed that in both cases, a comparison of both simulations with MODIS retrievals shows that the simulated Nd is considerably higher than the satellite data. It is plausible that the MODIS data may be influenced by the broken clouds, leading to an overestimation of the effective radius and consequently a lower Nd. In the Kilauea case, in LWP a relative enhancement by 14% inside the plume compared to outside the plume was obtained. However, in the La Soufrière eruption, the LWP inside the plume in the volcano and no-volcano simulations indicate that LWP does not differ significantly. In conclusion, the impact of volcanic eruption-induced aerosols on the LWP response is heavily influenced by cloud regimes. Also other model assumptions like the relevance of the precipitation formation rate as a cloud water sink play a role. However, in none of the simulations, a significant overall change in LWP that would have been plausibly consistent with observations was found.

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