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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.
31

A Review of Some Non-linear Evaluation Methods

Kanraj, Guru Prasath January 2022 (has links)
No description available.
32

Rekonstrukce paleo-environmentálních poměrů zaniklého jezera Šúr v pozdním glaciálu a holocénu pomocí analýzy makrozbytků / Reconstruction of palaeo-environmental conditions of a former lake Šúr during the late-glacial and Holocene using macrofossil analysis

Potůčková, Anna January 2014 (has links)
The Danubian Plain is nothern part of the Pannonian Plain and in terms of palaeobotanical research it is an entirely unexplored area. However, this region is assumed to contain cryptic glacial refugia and migration routes of thermophilous biota northward after the Last Glacial Maximum. The late-glacial and Holocene natural long-term succession and temporal changes in the composition of plant communities of lowland lakes in the Slovakia is unknown. Šúr, a National Nature Reserve is a former lake, presently overgrown by alder carr forest. Successional development since the late-glacial was studied along two profiles. Macrofossil analysis was carried out on lake sediments extending to the Middle Pleniglacial (OIS 3). Using knowledge of the modern ecological requirements of taxa, past environmental conditions were reconstructed. The historical biogeography of selected plant species in Europe during the late- glacial and Holocene is also discussed. During the Middle Pleniglacial Myriophyllum spicatum and Chara sp. grew in the lake. During the late-glacial shallow basin contained a calcareous, meso- to eutrophic lake with Potamogeton filiformis, P. praelongus, Ranunculus subgen. Batrachium etc. During the early Holocene these elements disappeared and thermophilous plants immigrated, such as the...
33

Non-photorealistic rendering with coherence for augmented reality

Chen, Jiajian 16 July 2012 (has links)
A seamless blending of the real and virtual worlds is key to increased immersion and improved user experiences for augmented reality (AR). Photorealistic and non-photorealistic rendering (NPR) are two ways to achieve this goal. Non-photorealistic rendering creates an abstract and stylized version of both the real and virtual world, making them indistinguishable. This could be particularly useful in some applications (e.g., AR/VR aided machine repair, or for virtual medical surgery) or for certain AR games with artistic stylization. Achieving temporal coherence is a key challenge for all NPR algorithms. Rendered results are temporally coherent when each frame smoothly and seamlessly transitions to the next one without visual flickering or artifacts that distract the eye from perceived smoothness. NPR algorithms with coherence are interesting in both general computer graphics and AR/VR areas. Rendering stylized AR without coherence processing causes the final results to be visually distracting. While various NPR algorithms with coherence support have been proposed in general graphics community for video processing, many of these algorithms require thorough analysis of all frames of the input video and cannot be directly applied to real-time AR applications. We have investigated existing NPR algorithms with coherence in both general graphics and AR/VR areas. These algorithms are divided into two categories: Model Space and Image Space. We present several NPR algorithms with coherence for AR: a watercolor inspired NPR algorithm, a painterly rendering algorithm, and NPR algorithms in the model space that can support several styling effects.
34

Régulation du cycle cellulaire par le récepteur natriurétique de type C dans les cellules du muscle lisse vasculaire : mécanismes moléculaires

El Andalousi, Jasmine 05 1900 (has links)
Nous avons précédemment montré que l’activation du récepteur natriurétique de type C (NPR-C) par son agoniste spécifique, le C-ANP4-23, atténue l’augmentation de la prolifération des cellules du muscle lisse vasculaire (CMLV) induite par les peptides vasoactifs (Ang II, ET-1 et l’AVP). Puisque les CMLV provenant de rats spontanément hypertendus (SHR) montrent elles aussi un taux de prolifération plus élevé que leur contrôle, les CMLV de rats Wystar-Kyoto (WKY), nous avons entrepris cette étude dans le but de déterminer si C-ANP4-23 peut également diminuer le taux élevé de prolifération des CMLV de SHR et, le cas échéant déterminer les mécanismes responsables de cette réponse. Nos résultats montrent que le taux de prolifération des CMLV de SHR est significativement plus élevé que celui des CMLV de WKY et que la présence de C-ANP4-23 diminue de manière-dose dépendante le taux de prolifération des CMLV de SHR. En plus, l’expression des protéines de la phase G1 du cycle cellulaire, la cycline D1, la kinase dépendante des cyclines 2 (cdk2) et la forme phosphorylée de la protéine du rétinoblastome (pRb) est augmentée dans les CMLV de SHR comparativement aux CMLV de WKY et est atténué par C-ANP4-23. De plus, nos résultats montrent que les inhibiteurs du complexe cycline D1/cdk4 (NSC 625987) et cdk2 (NU2058) diminue le taux de prolifération élevé des CMLV de SHR. Les CMLV de SHR montrent également un taux de phosphorylation de ERK1/2 et d’AKT et est atténué par C-ANP4-23. De plus, le taux d’expression élevé des protéines cycline D1, cdk2 et pRb des CMLV de SHR est diminué par la toxine pertussis qui inactive la protéine Giα, le PD 98095, un inhibiteur de MEK de la voie des MAPK, du wortmannin, un inhibiteur de la PI3-K et finalement du losartan, un antagoniste du récepteur AT1. Ces résultats suggèrent que l’activation du récepteur NPR-C par C-ANP4-23 diminue le taux de prolifération élevé des CMLV de SHR par une régulation à la baisse des composantes du cycle cellulaire via l’inhibition de la protéine Giα et des voies signalétique MAP kinase/PI3-K. / We have previously shown that natriuretic peptide receptor-C (NPR-C) activation by C-ANP4-23 decreased the proliferation of vascular smooth muscle cells (VSMC) induced by vasoactive peptides (Ang II, ET-1 and AVP). Since, VSMC from SHR also exhibit an enhanced proliferation as compared to VSMC from WKY, we undertook the present study to investigate if C-ANP4-23 could also attenuate the enhanced proliferation of VSMC from SHR and to further explore the underlying mechanisms responsible for this response. The proliferation of VSMC from SHR was significantly increased as compared to VSMC from WKY as determined by [3H]thymidine incorporation and was attenuated by C-ANP4-23 in a concentration-dependent manner. Furthermore the expression of cyclin D1, cyclin-dependent kinase 2 (cdk2) and phosphorylated retinoblastoma protein (pRb) was enhanced in VSMC from SHR compared to WKY which was attenuated by C-ANP4-23. In addition, the inhibitor of cdk4/cyclinD1 (NSC 625987) and cdk2 (NU2058) also attenuated the enhanced proliferation of VSMC from SHR in a concentration-dependent manner. VSMC from SHR also exhibited the enhanced phosphorylation of ERK1/2 and AKT as compared to WKY which was attenuated by C-ANP4-23.. Furthermore, the enhanced expression of cyclin D1, cdk2 and pRb in VSMC from SHR were also attenuated by pertussis toxin that inactivates Giα protein, PD 98095, a MEK kinase inhibitor, wortmannin, PI3K inhibitor as well as by losartan, an AT1 receptor antagonist. These results suggest that NPR-C activation attenuates the enhanced proliferation of VSMC from SHR which may be attributed to Giα /MAP kinase/PI3K-mediated inhibition of the expression of cell cycle components.
35

Struktura a vývoj autochtonních bukových porostů v CHKO Broumovsko. / Structure and development of autochthonous beech forests in the protected landscape area Broumovsko.

Gysin, Romana January 2016 (has links)
The thesis describes the horizontal and vertical structure of two permanent research plots with the developmental stages of the tree layer of native beech stands in NPR Broumov in the area CHKO Broumov nature reserve in the Sudetenland. The horizontal structure of the tree layer is random and in the developmental stages of natural regeneration. The average number of individuals natural recovery is around 15 100 individuals per hectare.
36

Regulação do sistema peptídeos natriuréticos nas células da granulosa e do cumulus na foliculogênese em bovinos / Regulation of the natriuretic peptide system in granulosa and cumulus cells in the folliculogenesis in bovine

De Cesaro, Matheus Pedrotti 10 March 2017 (has links)
This thesis aims to contribute to the knowledge of the regulation and function of the natriuretic peptide (NP) system during follicular dominance, ovulation, oocyte meiosis resumption and cumulus cells expansion in cattle. In the first study, the NP system was characterized in bovine COC. Moreover, NPPA and NPPC increased cGMP levels in cumulus cells and oocyte after 3 hours of culture, preventing the increase of cAMP in oocyte in the presence of forskolin. In the second study, using in vivo experimental models, none of the three NPs were detected in the granulosa cells during follicular deviation in cattle. However, NPR-3 is highly expressed at the expected time of follicular deviation, and all three NP receptors are expressed in granulosa cells of the dominant follicle. FSH injection maintained the expression of the three NP receptors after follicular deviation in the largest and second largest follicles. However, only NPR-1 mRNA decreased after inhibition of estradiol receptors by intrafollicular injection of fulvestrant. In the granulosa cells of pre ovulatory follicles, only NPPB mRNA was not detected. Nevertheless, after the administration of a GnRH analog, NPPC mRNA expression increased within 3 and 6 hours and NPR-3 mRNA gradually decreased after 3 hours. NPPA and NPR-2 mRNA was not regulated by GnRH, but NPR-1 mRNA increased at 24 hours after GnRH. In the third study, abundance of mRNA for NPR-1, NPR-2 and NPR-3 was not altered by LH and/or AG1478 (EGFr inhibitor) after 6 hours of culture in vitro. Also, LH stimulated NPPC mRNA expression and AG1478 prevented this increase in granulosa cultured in vitro. To confirm the in vitro results, was used an in vivo model and observed that the NPPC mRNA expression increased and NPR-3 mRNA decreased in granulosa cells after 6 hours of GnRH challenge. However, intrafollicular injection of AG1478 prevented the effect of GnRH on NPPC and NPR-3 mRNA expression. In addition, it we obseved that ANP in association with LH stimulated COX2 expression in comparison with LH alone or absence of this gonadotropin. It was observed that the EGFr blockade in vivo did not prevent ovulation in cattle. In the fourth study, it was observed that NPR-3 mRNA expression decreases in bovine cumulus cells after treatment of COCs with FSH or FSH+LH via EGFr. Forskolin, an adenylate cyclase stimulator, also decreased NPR-3 mRNA expression in cumulus cells. Expression of NPR-1 mRNA was very low in bovine cumulus cells and NPR-2 mRNA was not regulated in the proposed treatments. In addition, it was observed that the activation of NPR-3 by a specific agonist (cANP4-23) did not interfere in bovine oocyte nuclear maturation, but it inhibited the complete expansion of cumulus cells FSH+LH-stimulated. Additionally, the association of cANP4-23 with CNP further decreased cumulus cell expansion. / Esta tese tem como objetivo contribuir para o conhecimento da regulação e função do sistema dos peptídeos natriuréticos (NP) durante a dominância folicular, ovulação, retomada da meiose oocitária e expansão das células do cumulus em bovinos. No primeiro estudo, caracterizou-se o sistema NP no CCO de bovino e foi demonstrado que o NPPA e o NPPC aumentam os níveis de cGMP no cumulus e no oócito após 3 horas de cultivo, impedindo o aumento de cAMP no oócito na presença de forskolin. No segundo estudo, utilizando modelos experimentais in vivo, os três NPs não foram detectados nas células da granulosa durante a divergência folicular em bovinos. Contudo, demonstrou-se que o NPR-3 apresenta maior expressão no momento esperado da divergência folicular, sendo que após este momento os três receptores NPs apresentavam alta expressão nas células da granulosa do folículo dominante. A administração de FSH manteve a expressão dos três receptores NPs após a divergência folicular no maior e segundo maior folículo. Porém, somente a expressão do NPR-1 diminui após a inibição dos receptores de estradiol pela injeção intrafolicular de fulvestrant. Nas células da granulosa de folículos pré ovulatórios, somente o NPPB não foi detectado. De modo que, após a administração de um análogo de GnRH, a expressão de NPPC aumentou em 3 e 6 horas e a de NPR-3 gradualmente diminuiu após 3 horas. NPPA e NPR-2 não foram regulados pelo GnRH, e o NPR-1 teve a expressão aumentada somente 24 horas após o GnRH. No terceiro estudo, a abundância de mRNA para NPR-1, NPR-2 e NPR- 3 nas células da granulosa não foi alterada por LH e/ou por AG1478 (inibidor do EGFr) após 6 horas de cultivo in vitro. Também em cultivo in vitro de células da granulosa, o LH estimulou a expressão de NPPC, sendo que o AG1478 impediu este aumento. Como forma de comprovar esses resultados in vitro, utilizamos um modelo in vivo e observamos que a expressão do NPPC aumentou e a do NPR-3 diminuiu após 6 horas do desafio com GnRH, nas células da granulosa. De maneira que, a injeção intrafolicular de AG1478 preveniu o efeito do GnRH sobre a expressão do NPPC e NPR-3. Além disso, foi demonstrado que o ANP em associação com o LH estimulou a expressão de COX2 em comparação com LH isoladamente ou ausência desta gonadotrofina. Também foi demonstrado que o bloqueio do EGFr in vivo não foi suficiente para bloquear a ovulação em bovinos. No quarto estudo, foi observado que a expressão do NPR-3 diminui nas células do cumulus pelo tratamento dos CCOs com FSH ou FSH+LH via EGFr em bovinos. Forskolin (estimulador adenilato ciclase) também induziu a diminuição da expressão do NPR-3. A expressão do NPR-1 foi muito baixa no cumulus de bovino e o NPR-2 não apresentou regulação nos tratamentos propostos. Além disso, foi observado que a ativação do NPR-3 por um agonista específico (cANP4-23) não interferiu na maturação nuclear oocitária em bovinos, porém, inibiu a completa expansão das células do cumulus estimulada por FSH+LH. De maneira que, a associação do cANP4-23 com CNP potencializou a inibição da expansão das células do cumulus.
37

2D Aesthetics with a 3D Pipeline : Achieving a 2D Aesthetic with 3D Geometry

Nilsson, Morgan, Lundmark, Andreas January 2017 (has links)
This thesis evaluates and tests different methods utilized to produce a 2D aesthetic within a 3D pipeline, as in, converting 3D geometry to an aesthetic that is similar to hand-drawn classic films such as Snow White And The Seven Dwarfs. This thesis explores methods to produce both exterior and interior lines that indicate shape and form of 3D models, the conclusion from the tested methods leaves with the statement that it is unlikely the human factor will be ever entirely replaced by automated solutions, and instead a mixed approach with shader relied solutions and involvement of texturing techniques which provides artistic controls where necessary, is deemed to be the most effective way of preserving the hand-drawn 2D aesthetic within a 3D-pipeline.
38

Investigating hydrogeochemical processes of groundwater, Heuningnes Catchment, South Africa

Xaza, Abongile January 2020 (has links)
Masters of Science / This study was conducted to investigate hydrogeochemical processes controlling the evolution of groundwater chemistry and their influence on water quality in the Heuningnes Catchment. The role or influence of hydrogeochemical processes in groundwater quality in aquifer systems remains poorly understood. One of the ways of improving such understanding is to employ different techniques to explore key processes that govern groundwater quality in aquifer systems. Therefore, the present study investigated hydrogeochemical processes of groundwater resources and identified key processes that explained its quality from a spatiotemporal perspective. The quantitative approach that provides the ability to assess relationships between variables both spatially and temporally was applied. Groundwater sampling was done on four occasions during July 2017, October 2017, March 2018, and July 2018. Identification of hydrogeochemical processes controlling the evolution of groundwater chemistry and quality was done using various complementary tools. These tools included classification of the main water types, evaluation of water-rock interaction by means of stoichiometry analysis and bivariate correlation plots, inverse geochemical modelling, and statistical analysis (hierarchical cluster analysis and factor analysis). Physical parameters were measured in situ, while water samples were collected from boreholes, piezometers, springs, and artesian boreholes for laboratory analysis for major ions analysis. Descriptive and bivariate statistical methods were used to summarise and evaluate the strength of the relationship between variables, while multivariate statistical methods were applied to group similar samples based on their chemical compositions. Tri linear Piper diagrams were generated to characterize water type based on double normalizing the proportions of cations and anions, while correlation and stoichiometric analysis were applied to identify hydrogeochemical processes influencing groundwater chemistry. The results generated from the trilinear Piper diagrams confirmed the dominance of sodium and chloride ions in waters of the Heuningnes Catchment. Groundwater of a Na/Cl type is typical for a coastal aquifer characterised by saline, deep ancient groundwater. The lower parts of the Catchment were characterised by saline groundwater. The results indicated that shallow groundwater samples within the study area were more mineralised as compared to deep groundwater with EC values ranging between 20.8 and 2990 mS/m, with waters within the Table Mountain Group region (TMG), recording the lowest values. Deep groundwater for boreholes and artesian boreholes located upstream in the Catchment was fresh and yielded some of the lowest EC values recorded with an EC value below 50 mS/m. Generally, EC values increased from the upper TMG region of the Catchment towards the Bokkeveld shale region downstream and were highest during the dry season of 2018. The results indicated strong geological influences on water chemistry. Bivariate correlation and stoichiometric analysis identified cation exchange, adsorption, evaporation, weathering of carbonates, sulphates and silicate minerals as processes influencing the chemistry of groundwater in the Heuningnes Catchment. The Saturation Index (SI) results showed a change of calcite, dolomite, aragonite, gypsum, anhydrite, halite, melantinterite, siderite and sylvite from being undersaturated to oversaturated at some areas for the different seasons along the flow path. The mass-balance modelling results indicated that ion exchange and reverse ion exchange processes were more dominant at low elevations along the same flow path during the dry periods. However, at high elevations along the flow path, silicate weathering was the dominant process taking place. The findings of this study demonstrated the influence of hydrogeochemical processes in changing the water chemistry along the flow paths. In conclusion, the study showed the value of utilising various assessment tools as complementary techniques to improve the understanding about hydrogeochemical processes, and its influence on evolution of groundwater chemistry and quality. Based on the findings of the study the following recommendations were made for future studies; the sample points or sample boreholes in the study Catchment should be increased; and to have more sampling trips to enable better comparison between the possible processes
39

Kvartérní paleoekologická analýza NPR Soos / The Quaternary Paleoecological Analysis of the Soos National Nature Reserve

Rajdlová, Hana January 2011 (has links)
The Quaternary Paleoecological Analysis of the Soos National Nature Reserve The aim of this proposed diploma thesis is to describe the structure of diatom communities in the diatomite deposits of the Soos National Nature Reserve and compare the finding of this thesis with those of older publications. Another aim was to reconstruct the history of the basin trough with the outputs of diatom analysis accomplished in the 3,4 m long sediment profile. The similarity of diatom communites in individual diatomite types was also tested. Key words: subfossil diatoms, Soos National Nature Reserve, paleolimnology, Late Glacial, Holocene
40

Régulation du cycle cellulaire par le récepteur natriurétique de type C dans les cellules du muscle lisse vasculaire : mécanismes moléculaires

El Andalousi, Jasmine 05 1900 (has links)
No description available.

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