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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

Joint iterative channel and data estimation in high mobility MIMO-OFDM systems

Sand, Stephan January 2009 (has links)
Zugl.: Zürich, Techn. Hochsch., Diss., 2009 / Fälschl. als Bd. 6 der Schriftenreihe bezeichnet
32

Ανάπτυξη μορφής για κολπική χορήγηση του φαρμάκου MC-1220

Μουρτάς, Σπυρίδων 27 December 2010 (has links)
Προκειμένου να παρεμποδιστεί διάδοση του σεξουαλικά μεταδιδόμενου HIV είναι απαραίτητη η ανάπτυξη κατάλληλης κολπικής φαρμακομορφής για τοπική χορήγηση η οποία θα αποτρέπει την μετάδοση του ιού σε υγιείς ανθρώπους. Το κολπικό αυτό σκεύασμα είναι σημαντικό να αποτελείται από κατάλληλη βιολογικώς δραστική ουσία και ως τέτοια μπορεί να θεωρηθεί το MC-1220 και το δραστικό (R)-εναντιομερές του (MC-εναντιομερές). Πρόκειται για μικροβιοκτόνα της κατηγορίας των DABOs (3,4-Dihyro-2-Alkoxy-6-Benzyl-4-OxopyrimidineS–DABOs) αναστολέων και ανήκουν στην κατηγορία των μη-νουκλεοτιδικών αναστολέων της αντίστροφης μεταγραφάσης (NNRTI). Η εξαιρετικά χαμηλή διαλυτότητα του MC σε υδατικά διαλύματα (< 3 ppm) μας οδήγησε στην ανάπτυξη μικρογαλακτωμάτων των MC και MC-εναντιομερούς. Τα μικρογαλακτώματα αυτά χρησιμοποιήθηκαν για την παρασκευή φαρμακομορφών (απλές γέλες) στις οποίες η συγκέντρωση του MC και MC-εναντιομερούς ήταν ~1.000 και 7.000 ppm αντίστοιχα. Αντιθέτως η ανάπτυξη κατάλληλης λιποσωμικής μορφής του MC (DRV_HPC/Chol(2:1) λιποσώματα) με υψηλές τιμές εγκλωβισμού MC, μας έδωσε την δυνατότητα παρασκευής τελικών σκευασμάτων (σύνθετες - λιποσωμικές γέλες) με εξαιρετικά υψηλές συγκεντρώσεις MC (~15.000 ppm). Επιπλέον και προκειμένου να αυξηθεί η συγκέντρωση του MC στις τελικές φαρμακομορφές (λιποσωμικές γέλες), αναπτύχθηκαν σύμπλοκα υδροξυπροπυλ-β-κυκλοδεξτρίνης/MC (HP-β-CD/MC), τα οποία επίσης ενσωματώθηκαν κατάλληλα στις τελικές λιποσωμικές φαρμακομορφές. Τέλος αναπτύχθηκαν κατάλληλες in vitro μέθοδοι, προκειμένου να γίνει συγκριτική αξιολόγηση των νέων φαρμακομορφών, ως προς την δυνατότητα σταδιακής αποδέσμευσης του MC στην περιοχή ενδιαφέροντος. Οι νέες φαρμακομορφές μελετήθηκαν in vivo σε πειραματόζωα (μακάκους), με ιδιαίτερα επιτυχή αποτελέσματα ως προς την πρόληψη και θεραπεία από τον HIV. / -
33

Ověření pravosti označení taxonů rodu Origanum L. pomocí metod GC-MC a AFLP

Hradská, Lucie January 2015 (has links)
The aim was to verify the authenticity marking taxa genus Origanum L. The sortments were grown at the experimental plots ZF MENDELU in 2014. The analysis of the evaluation results of the work carriedout was laso done in the same year. The assortments were morphological described. The morphological characters were such as: plant height, leaf size, inflorescence height, color of the leaves and flowers. Further details were recorded on phenological phases of the taxa. Oregano samples were assessed for quantity of essential oils by distillation and the essential oils was then subjected to qualitative evaluation using the GC-MC method. The genetic relationships were evaluated using the AFLP methods.
34

Epigenetic modification of mitochondrial genes in Alzheimer's disease (AD)

Devall, Matthew Adrian Michael January 2017 (has links)
Alzheimer’s disease is a chronic, neurodegenerative disease characterised by amyloid plaque accumulation, neurofibrillary tangles and eventual neuronal cell loss. The complex aetiology exhibited in late-onset Alzheimer’s disease presents a considerable challenge in the field of genetics, with identified variants from genome-wide association studies collectively only explaining about a third of disease incidence. As such, new avenues are being explored to elucidate underlying mechanisms associated with disease onset and progression. In 2014, the first epigenome-wide association studies in Alzheimer’s disease were published, identifying several, novel differentially methylated loci in the nuclear genome in cortical brain samples, highlighting that epigenetic mechanisms may play a role in disease aetiology. Further, a growing body of evidence has implicated mitochondrial dysfunction as an early feature of disease pathogenesis. Despite this, few studies have investigated the role of mitochondrial DNA epigenetics in Alzheimer’s disease. Indeed, the relatively nascent field of mitochondrial epigenetics has largely been restricted to candidate-based gene approaches to identify differential methylation associated with disease. The main aim of this thesis was therefore to design an experimental and bioinformatic pipeline for the analysis of mitochondrial DNA methylation in post- mortem human brain tissue; first in healthy non-demented control donors, and subsequently in individuals with Alzheimer’s disease. Our work therefore represents the first epigenome wide studies of mitochondrial DNA methylation at single nucleotide resolution, providing a framework not only for mitochondrial DNA methylation in Alzheimer’s disease, but also in a number of complex diseases characterised by mitochondrial dysfunction.
35

Zirconium isotope heterogeneities in the solar system

Akram, Waheed January 2013 (has links)
Laboratory measurements of primitive and differentiated meteorites have been made in order to understand the origin of isotopic anomalies. The element Zr is chosen for analysis, due to its potential for nuclear and astrophysical applications. Zirconium has five stable isotopes that are produced in different (neutron–capture) nucleosynthetic processes. By analysing the Zr isotope composition of meteorites, we are able to track the mixing of various neutron capture processes in the early Solar System. Measurements have been performed on carbonaceous, ordinary and enstatite chondrites, eucrites, the Moon and Earth. Samples are crushed, digested and passed through a two stage anion exchange separation to obtain a clean Zr fraction. All Zr measurements are made on a Nu Plasma multiple–collector inductively coupled plasma mass spectrometer (MC–ICPMS). The results indicate that the bulk of refractory Ca–Al rich inclusions of the Allende meteorite are characterised by uniform enrichments (around 2ε) of the neutron–rich isotope 96Zr, and potentially coupled with excesses reported for the neutron rich isotope 50Ti, indicating that both nuclides may have similar astrophysical origins. Analysis of bulk rock carbonaceous chondrites reveal 96Zr excesses (not exceeding 1ε) that scale with the abundance of CAIs. However, widespread 96Zr correlations are also seen, accompanied by minor depletions in 91Zr, which suggest the solar nebular had experienced thermal heating of some sort, altering the initial (possibly uniform) Zr isotope composition of the early Solar System from which planetary bodies formed.
36

Algoritmy pro řízení elektrických motorů / Algorithms for electrical motor control

Lyko, Antonín January 2017 (has links)
This paper presents the structure and basic elements of the Autosar software architecture. In addition, the configuration code generation options are presented for both MC-ISAR drivers and AURIX TriCore TC277 hardware modules using EB tresos Studio. For the purpose of possible integration of the electric motor control algorithms, configurations of the GTM and VADC hardware modules have been created and described to enable the generation of PWM signals along with synchronously triggered parallel analogue-to-digital conversions. For this purpose, an application interface including the PWM driver was also developed and described.
37

Fasciolosis en vicuñas (vicugna vicugna) en el distrito de Paccha, provincia de Yauli – Junín

Samamé Arrieta, Luis Miguel January 2014 (has links)
El objetivo del presente estudio fue determinar la presencia de huevos de Fasciola hepatica en vicuñas en el distrito de Paccha, provincia de Yauli – Junín, así como, estimar la frecuencia y determinar la asociación con las variables sexo y estrato etario; además determinar la carga parasitaria (hpg). Considerando que se tratan de animales silvestres, se tomaron muestras del mayor número de vicuñas posibles provenientes de un chaccu realizado durante la época de esquila en el mes de setiembre del 2010. Las muestras de heces fueron tomadas directamente del recto de los animales, siendo almacenadas y conservadas en refrigeración a 4ºC para su traslado y evaluación en el Laboratorio de Parasitología de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos. El diagnóstico de la frecuencia de F. hepatica se realizó mediante la técnica de sedimentación rápida y la determinación de la carga parasitaria, huevos por gramo de heces (hpg), mediante el método de Mc Master modificado. Se encontró una frecuencia de F. hepatica del 32.9%. Respecto a la variable sexo, se halló frecuencias en macho y hembra del 35.8 y 29% respectivamente, y respecto a la variable estrato etario, las frecuencias en cría, juvenil y adulto fueron de 5.6, 45.7 y 33.3 % respectivamente. No se encontró diferencia significativa (p<0.05%) entre las variables sexo, sin embargo, hubo asociación significativa con la variable estrato etario, donde los animales juveniles presentaron un alta frecuencia. La carga promedio fue de 23.7 hpg. / Tesis
38

Using Rapid Small Scale Column Testing to Evaluate Granular Activated Carbon Adsorption of Cyanotoxins from Drinking Water

Kelley, Thomas M. January 2017 (has links)
No description available.
39

Beamforming for MC-CDMA

Venkatasubramanian, Ramasamy 10 March 2003 (has links)
Orthogonal Frequency Division Multiplexing (OFDM) has recently gained a lot of attention and is a potential candidate for Fourth Generation (4G) wireless systems because it promises data rates up to 10Mbps. A variation of OFDM is Multi-Carrier CDMA (MC-CDMA) which is an OFDM technique where the individual data symbols are spread using a spreading code in the frequency domain. The spreading code associated with MC-CDMA provides multiple access technique as well as interference suppression. Often times in cellular and military environments the desired signal can be buried below interference. In such conditions, the processing gain associated with the spreading cannot provide the needed interference suppression. This research work investigates multi-antenna receivers for OFDM and MC-CDMA systems; specifically this works investigates adaptive antenna algorithms for MC-CDMA for very different channel conditions. Frequency domain beamforming is studied in this research predominantly through simulation. As an alternative a time domain beamforming is also studied. Time variations in the channel can disrupt the orthogonality between subcarriers. Minimum Mean Square Error (MMSE) detection coupled with MMSE beamforming is proposed for time varying channels. Semi-analytic results are derived to study the Bit Error Rate (BER) performance. These results show significant performance improvement in the presence of interference. Joint MMSE weights in space and frequency is also investigated and semi-analytic results are derived to study their BER performance. / Master of Science
40

Germanium and related elements in sulphide minerals : crystal chemistry, incorporation and isotope fractionation / Germanium et éléments associés dans les sulfures : cristallochimie, modes d’incorporation et fractionnement isotopique

Belissont, Rémi 15 March 2016 (has links)
Le germanium est un métalloïde « stratégique » dans l’industrie high-tech, notamment pour la transition énergétique et le secteur des communications. Étant distinctement sidérophile, lithophile, chalcophile et organophile, le Ge possède un fort potentiel comme traceur géochimique. Ces travaux de thèse visent à améliorer la compréhension de la géochimie du cycle du Ge et des facteurs qui contrôlent son incorporation dans les minéraux et les gisements métalliques. Les cibles de cette étude concernent le gisement filonien à Zn de Saint-Salvy (Massif Central, France), le gisement filonien à Cu de Barrigão (Ceinture pyriteuse ibérique, Portugal), et le gisement à Zn–Cu de Kipushi (R.D. Congo). Les porteurs de Ge les plus importants sont respectivement la sphalérite (jusqu’à 2580 ppm), la chalcopyrite (jusqu’à 5750 ppm) et la réniérite (5,0–9,1 %). Les résultats montrent qu’il existe une relation de premier ordre entre la concentration en Ge dans la sphalérite et le type de gisement. La spectroscopie XANES par rayonnement synchrotron met en évidence la présence de Ge4+ en site tétraédrique dans les sulfures analysés. Les corrélations élémentaires observées dans la sphalérite et la chalcopyrite suggèrent une incorporation du Ge par co-substitutions, e.g., 3Zn2+ ↔ Ge4+ + 2(Cu,Ag)+ et 3Fe3+ ↔ 2Ge4+ + Cu+, ou via la création de lacunes cristallographiques, e.g., 2Zn2+ ↔ Ge4+ + ?. La corrélation positive δ74Ge–[Ge]ZnS des sphalérites de Saint-Salvy indiquerait que coefficient de partage (KdGe) augmenterai avec T. Les compositions isotopiques δ74Ge des sulfures étudiés varient de –5,72‰ à +3,67‰. Les compositions légères mesurées dans les gisements de Saint-Salvy et Barrigão semblent liées à des variations de température des fluides (basse à moyennes T) lors de l’incorporation de Ge en système ouvert, alors que la tendance marquée vers les compositions isotopiques lourdes à Kipushi indiquerait un fractionnement de Rayleigh. / Germanium is a critical metalloid in many high-tech industries, especially for the energy transition and the communication sector. Being distinctly siderophile, lithophile, chalcophile and organophile, Ge can be a particularly useful geochemical tracer. This thesis aims at understanding the Ge geochemistry and the factors controlling its concentration in Ge-bearing minerals and ore deposits. Three contrasted Ge-bearing deposits were studied, the Saint-Salvy Zn vein-type deposit, French Massif Central, the Barrigão Cu vein-type deposit, Iberian pyrite belt, Portugal, and the Kipushi Zn–Cu carbonate-hosted deposit, Central African copper-belt, D.R. Congo. The most important Ge-bearing minerals are sphalerite (up to 2580 ppm Ge), chalcopyrite (up to 5750 ppm Ge), and renierite (5.0–9.1 wt.% Ge). The results show a first order relation between the Ge content and the deposition temperature. Synchrotron-based XANES spectroscopy showed that Ge4+ occur in tetrahedral sites in the studied sulphides. Element correlations suggest that Ge is chiefly incorporated in sphalerite and chalcopyrite through coupled substitutions, e.g., 3Zn2+ ↔ Ge4+ + 2(Cu,Ag)+ and 3Fe3+ ↔ 2Ge4+ + Cu+, respectively, or via the creation of lattice vacancies, e.g., 2Zn2+ ↔ Ge4+ + ?. The positive δ74Ge–Ge content correlation observed in sphalerite from Saint-Salvy could indicate that Ge partition coefficient (KdGe) increases with temperature. Ge isotopes in sulphides yield δ74Ge values spanning from –5.72‰ to +3.67‰. The light δ74Ge compositions of Saint-Salvy and Barrigão ores appear to be related to variations in low to moderate fluid temperatures during Ge uptake in open system (e.g., fluid cooling), while the trend towards heavy δ74Ge compositions observed at Kipushi likely translates a Rayleigh fractionation effect during ore formation in closed system, associated with significant fluid modification.

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