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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.
301

Mitochondrial DNA in sensitive forensic analysis /

Nilsson, Martina, January 2007 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2007. / Härtill 5 uppsatser.
302

Determinação do perfil de compostos fenólicos na própolis vermelha de Alagoas usando técnicas de fingerprinting (impressão digital) com LC-Orbitrap-FTMS e o software MZmine. / Determination of the profile of phenolic compounds in red propolis of Alagoas using fingerprinting techniques with LC-Orbitrap-FTMS and MZmine software

Souza, Naiana Soares de 15 August 2014 (has links)
Red Propolis northeastern Brazil (Alagoas, Brazil) has been widely studied for their biological activity against parasites, microorganisms. The composition of propolis varies according to geographic region and seasonality. Currently only isoflavanas, isoflavones and some propolones / guttiferones identified in propolis in Alagoas. The aim of this study was to apply modern methods of analysis of fingerprinting and screening (Screening), using LC-Orbitrap-FTMS in combination with MZmine software for extracting data from molecular ions to carry out such studies of propolis. Four propolis samples collected in two different towns of state of Alagoas and two of Pernambuco -. Brazil in the month of June / July 2012 The 2 samples of red propolis originating Alagoas (5.0 g) were subjected to extraction with ethanol to obtain their crude extracts, the remaining sample were already sold in the form of crude extract. The extracts solubilized in ethanol, diluted to a concentration of 1mg/mL, and injected directly into the LC-Orbitrap-FTMS, MS data extracted using the software MZmine 02.10. The precise masses of the components of the extracts compared with a database of online data. The LC-FTMS analysis combined with extraction and search database online with MZmine showed the presence of over 2,000 ion in the extract but only 210 could be a probable identification. In the Histogram, analysis showed phenolic groups/chalcones acids; isoflavones/isoflavans/ pterocarpans; propolones/guttiferones/bflavonoids specific mass of bands of common substances such as propolis, present as major compounds. Samples showed differences in the chemical profile, but all showed a high frequency of propolonas, isoflavones, terpenes and guttiferones / terpenosideos. Software MZmine and techniques of LC-FTMS and are extremely applicable for the testing fingerprint and identification of new phenolic compounds, not idetificavéis by conventional techniques phytochemical present in complex matrices. / Fundação de Amparo a Pesquisa do Estado de Alagoas / A Própolis vermelha do nordeste brasileiro (Alagoas, Brasil) tem sido amplamente pesquisada por sua atividade biológica contra diversos tipos de microrganismos. A composição da própolis varia de acordo com a região geográfica e a sazonalidade. Atualmente isoflavonoides e algumas propolonas/guttiferonas foram identificados na própolis vermelha de Alagoas. O objetivo deste estudo foi aplicar métodos modernos de análise de Impressão digital e triagem (Screening), usando LC-Orbitrap-FTMS em combinação com o software MZmine para a extração de dados dos íons. Quatro amostras de própolis foram coletadas: duas na cidade Marechal Deodoro no estado de Alagoas e duas na cidade de Igarassu no estado de Pernambuco – Brasil durante o mês de Junho/Julho de 2012. As amostras de Própolis vermelha de Alagoas, cinco gramas de cada amostra, foram submetidas a extração com etanol para obtenção de seus extratos brutos, as demais foram cedidas sob a forma de extrato bruto. Os extratos foram solubilizados em etanol e diluídos para a concentração de 1mg/mL e injetados diretamente no LC-Orbitrap-FTMS. Os dados de MS foram extraídos usando o software MZmine 2.10. As Massas exatas dos componentes dos extratos foram comparadas com um banco de dados on-line. A análise de LC-FTMS combinada com extração e pesquisa em banco de dados on-line com MZmine demonstrou presença de mais de 2.000 íons no extrato, onde 210 puderam ter uma identificação provável. A análise do Histograma de frequência íons mostrou agrupamentos de ácidos fenólicos/chalconas; isoflavonoides/ isoflavanas/pterocarpanos; propolonas/guttiferonas/ biflavonoides em faixas de massas específicas como substâncias comuns a própolis vermelha e presentes como substâncias majoritárias. Apesar das amostras apresentarem diferenças no perfil químico, todas continham alta frequência dos agrupamentos vistos no histograma. O software MZmine e as técnicas de LC-FTMS são extremamente aplicavéis para identificação de novos compostos fenólicos, não idetificavéis por técnicas convencionais de fitoquímica presentes em matrizes complexas.
303

The constitutionality of the Criminal Law (Forensic Procedures) Amendment Act

Laing, Samantha Robyn January 2017 (has links)
The Criminal Law (Forensic Procedures) Amendment Act 37 of 2013 came into operation in January 2015. The Act makes provision for the establishment of a National Forensic DNA Database, which will store DNA profiles of certain groups of people. This research will discuss the establishment of a forensic DNA database in South Africa. The legal position in the United States of America will also be considered, with specific reference to the states of Maryland, California and New York. This research will focus predominantly on the collection of DNA samples and profiles from arrestees. When such samples are allowed to be collected, what offences warrant the collection of such samples and the period within which the DNA samples need to be destroyed. Collecting DNA samples and profiles from certain persons could potentially violate particular rights in the Bill of Rights. The rights to privacy, bodily integrity, equality and human dignity are discussed as well as the approach the courts have adopted in dealing with such infringements or possible infringements. This research furthermore deals with the historical developments of DNA evidence and contains a brief discussion on expert evidence. This research also deals with the evidential value of DNA evidence, as well as possible problems faced by prosecutors and defence attorneys when dealing with DNA evidence. The Criminal Law (Forensic Procedures) Amendment Act is still very new, and therefore, there is not yet much case law in South Africa specifically dealing with the sections of the said Act. This research makes submissions and recommendations regarding certain sections of the Act, as well as the overall constitutionality of the Act.
304

Development of a statistical framework for mass spectrometry data analysis in untargeted Metabolomics studies

Kaever, Alexander 06 June 2014 (has links)
No description available.
305

Ruissellement et éronsion hydrique en milieu méditerranéen vertique : approche expérimentale et modélisation / Runoff and water erosion in mediterranean cultivated vertisols : experimental and modeling approach

Inoubli, Nesrine 08 July 2016 (has links)
L'érosion hydrique constitue un phénomène complexe très répandu en contexte méditerranéen du fait d'une combinaison de facteurs souvent défavorables. Elle constitue une menace pour les potentialités en eau et en sol de ces régions. Si les facteurs déterminants de l'érosion hydrique sont aujourd'hui bien identifiés, la hiérarchie des processus en jeu en fonction des échelles d'espace et de temps est encore très mal connue. Les sols vertiques, qui occupent des surfaces importantes dans la région Méditerranéenne, apportent un degré supplémentaire de complexité du fait de la forte dynamique structurale de ces sols. Dans ce contexte, cette étude cherche à mieux appréhender la variabilité spatio-temporelle des processus et facteurs affectant les transferts latéraux d’eau et de sédiments dans un bassin versant agricole dominés par les vertisols. Pour cela, 7 années de mesures (2005-2012) des ruissellements et transferts de matières en suspension au sein du bassin versant de Kamech (ORE OMERE, 263 ha, Cap Bon, Tunis) ont été analysées au niveau de 4 stations hydrologiques: 1/ l'exutoire d'une parcelle (1,32 ha) ; 2/ l'exutoire d'une ravine (0,17 ha) alimentée par une parcelle de 1,20 ha ; 3/ l'exutoire du versant (15,2 ha) intégrant les deux stations précédentes, et 4/ la station de l’oued (175 ha) située dans le drain principal alimentant la retenue de Kamech. L’analyse des données a permis de mettre en évidence le rôle majeur des fentes de retrait sur la dynamique saisonnière des flux hydro-sédimentaires avec comme résultat un décalage entre le pic de flux de sédiments observé entre octobre et décembre et le pic de flux de ruissellement observé entre décembre et mars, et ce quel que soit l’échelle spatiale considérée. Les données expérimentales ont également permis de mettre en évidence une légère augmentation du ruissellement moyen annuel avec l’accroissement de l’échelle spatiale avec 95 mm/an pour la parcelle, 105 mm/an pour la ravine et 120 mm/an pour le versant. Cette augmentation peut s'expliquer par l'apparition de petites surfaces moins infiltrantes lorsque l'on passe de la parcelle aux autres stations. Les différences de taux d'érosion moyens annuels observées entre les échelles spatiales ont pu être été expliquées par un simple modèle linéaire combinant un taux unique d'érosion des surfaces cultivées (17 t ha-1 an-1) et un taux unique d'érosion ravinaire (80 t ha-1 an-1), pondérés par les surfaces respectives de ces deux éléments. La technique de traçage des sources de sédiments mise en place sur des sédiments prélevés au cours de quelques crues au niveau des différentes stations a permis de montrer que la contribution des processus responsables du transfert de sédiments était relativement stable au cours de l'année. L’application de la fonction de production de Morel-Seytoux a permis de reproduire les hydrogrammes mesurés à la parcelle pour la plupart des crues, indépendamment de la présence ou non des fentes de retrait. Par contre l’évolution des deux paramètres de ce modèle (conductivité hydraulique à saturation et facteur de stockage et de succion) en fonction de la présence des fentes de retrait, de l’état de surface du sol et du degré d’humidité reste à modéliser. Ce travail permet de conclure que le bassin versant de Kamech est caractérisé par une très forte connectivité hydro-sédimentaire, que les processus d’érosion diffuse y prédominent et que les actions de lutte anti-érosive doivent être ciblées avant tout au niveau des parcelles agricoles avec une attention particulière pour la période d’octobre à décembre. Ce travail a également permis de mettre en évidence le rôle déterminant des fentes de retrait sur la dynamique hydro-sédimentaire des bassins sur sol vertique et la nécessité de poursuivre l’étude de leur impact pour des fins de modélisation et d’aide à la gestion de ces milieux. / As one of the major types of land degradation, soil erosion by water induced large-scale environmental deterioration and declines in land productivity, especially in the Mediterranean area. If water erosion factors are now well known, the complex hierarchy of erosion processes over a wide range of spatial and temporal scales still needs to be studied. Shrink–swell soils that are widespread under Mediterranean climate, imply additional changes in terms of hydrological and erosive responses in relation to the changing soil water conditions. In this context, this study aims to better understand the processes and factors affecting the lateral transfers of water and sediments in an agricultural catchment dominated by vertisols under a range of spatial and temporal scales. A detailed monitoring investigation was conducted in the Kamech catchment (ORE OMERE, Tunisia) that includes continuous runoff and suspended sediment load measurement between 2005 and 2012 at the outlet of a four hydrological gauging stations: 1/ a plot (1.32 ha), 2/ a gully (0.17 ha) in which drains a 1.20 ha plot; 3/ a micro-catchment (15.2 ha) integrating the two previous stations and 4/ the oued station (175 ha) located in the main drain just upstream the Kamech reservoir. Data analysis showed that topsoil cracks appeared to seriously affect the seasonal dynamics of water and sediment delivery whatever the considered spatial scale. A similar time lag in the seasonality between water and sediments delivery was observed: although the runoff rates were globally low during the presence of topsoil cracks in autumn, most sediment transport occurred during this period because of very high sediment concentrations. Mean annual runoff proved to slightly increase with the scale area with 95 mm/year for the plot, 105 mm/ year for the gully and 120mm/year for the micro-catchment station. Increase of area with low infiltration capacity when moving from plot to micro-catchment has been identified as a major explanation of this increase. A simple linear model combining a single rate of topsoil erosion (17 t ha-1 yr-1) and a single rate of gully erosion (80 t ha-1 yr-1) -weighted by their respective surface area- has successfully reproduced the differences observed in the mean annual erosion rates between the spatial scales. The sediment fingerprinting method applied on sediments collected during four flood events at the different stations showed that the apportionment of the processes responsible for the transfer of sediments was relatively stable during the year. The application of the Morel-Seytoux infiltration model has allowed reproducing runoff measured at the parcel outlet for most of the events, whatever the presence of cracks or not. However, the evolution of the two parameters in this model (the saturated hydraulic conductivity and the storage-suction factor) as a function of the presence of the cracks, of the soil surface conditions and of the degree of humidity still need to be modelled. This work allows concluding that the Kamech catchment is characterized by a very high hydro-sedimentary connectivity and a predominance of topsoil erosion processes and that the implementation of erosion control measures should incentivize farming conservation practices focusing especially on the autumn period. This work also highlights the crucial role of the cracks on the catchment runoff and sediment dynamics in Mediterranean vertisol context and the need to better understand and model both the runoff and soil erosion processes associated with cracking soils environment.
306

Applications of Molecular Genetics to Human Identity.

Turnbough, Meredith A. 12 1900 (has links)
The primary objectives of this project were: 1. to develop improved methods for extraction of DNA from human skeletal remains, 2. to improve STR profiling success of low-copy DNA samples by employing whole genome amplification to amplify the total pool of DNA prior to STR analysis, and 3. to improve STR profiling success of damaged DNA templates by using DNA repair enzymes to reduce the number/severity of lesions that interfere with STR profiling. The data from this study support the following conclusions. Inhibitory compounds must be removed prior to enzymatic amplification; either during bone section pretreatment or by the DNA extraction method. Overall, bleach outperformed UV as a pretreatment and DNA extraction using silica outperformed microconcentration and organic extraction. DNA repair with PreCR™ A outperformed both whole genome amplification and repair with PreCR™ T6. Superior DNA extraction results were achieved using the A6 PMB columns (20 ml capacity column with 6 layers of type A glass fiber filter), and DNA repair with PreCR™ A led to an overall improvement in profile quality in most cases, although whole genome amplification was unsuccessful. Rapid, robust DNA isolation, successful amplification of loci from the sample-derived DNA pool, and an elimination of DNA damage and inhibitors may assist in providing sufficient genetic information from cases that might otherwise lie on the fringe of what is possible to obtain today.
307

Natural Fingerprinting of Steel

Strömbom, Johannes January 2021 (has links)
A cornerstone in the industry's ongoing digital revolution, which is sometimes referred to as Industry 4.0, is the ability to trace products not only within the own production line but also throughout the remaining lifetime of the products. Traditionally, this is done by labeling products with, for instance, bar codes or radio-frequency identification (RFID) tags. In recent years, using the structure of the product itself as a unique identifier, a "fingerprint", has become a popular area of research. The purpose of this work was to develop software for an identification system using laser speckles as a unique identifier of steel components. Laser speckles, or simply speckles, are generated by illuminating a rough surface with coherent light, typically laser light. As the light is reflected, the granular pattern known as speckles can be seen by an observer. The complex nature of a speckle pattern together with its sensitivity to changes in the setup makes it robust against false-positive identifications and almost impossible to counterfeit. Because of this, speckles are suitable to be used as unique identifiers. In this work, three different identification algorithms have been tested in both simulations and experiments. The tested algorithms included one correlation-based, one method based on local feature extraction, and one method based on global feature extraction. The results showed that the correlation-based identification is most robust against speckle decorrelation, i.e changes in the speckle pattern, while being quite computationally expensive. The local feature-based method was shown to be unfit for this current application due to its sensitivity to speckle decorrelation and erroneous results. The global feature extraction method achieved high accuracy and fast computational speed when combined with a clustering method based on overlapping speckle patterns and a k-nearest neighbours (k-NN) search. In all the investigated methods, parallel calculations can be utilized to increase the computational speed.
308

Přenos bezpečnostních opatření z prohlížeče Brave do rozšíření JavaScript Restrictor / Porting of Brave Fingerprinting Protection to JavaScript Restrictor

Švancár, Matúš January 2021 (has links)
Users of internet browsers are constantly monitored, without their consent. By using the JavaScript APIs, it is possible to obtain various information about the browser, which together form a browser fingerprint, which can then be misused. Therefore, the goal of this work is to use a robust fingerprint protection solution of Brave browser and port it to the JavaScript Restrictor extension. In this work, the problematics of obtaining an fingerprint and countermeasures in the Brave browser are analyzed and then compared with the current protection in the JSR extension. The method of porting of Brave's countermeasures is presented and subsequently the procedure of implementation of these defense elements into the browser extension is described. The resulting implementation has been tested and evaluated, with the new protection appearing to be effective.
309

Sources et dynamiques spatiales et temporelles des contaminations en éléments traces et hydrocarbures aromatiques polycycliques du continuum atmosphère - sol - rivière d'un bassin versant contrasté / Sources and spatial and temporal dynamics of trace elements and polycyclic aromatic hydrocarbons contamination in the atmosphere – soil – river continuum of a contrasted catchment

Froger, Claire 18 October 2018 (has links)
Le développement des activités humaines, notamment industrielles, depuis le 19ième siècle a engendré une contamination massive de l’atmosphère à la rivière, en passant par la biosphère et les sols. Si les contaminations ont fortement diminué depuis la fin des années 1960, elles persistent notamment en milieu urbain, où se concentrent un grand nombre d’activités humaines. Afin de pouvoir gérer au mieux la pollution, il est nécessaire de comprendre la dynamique de transfert des contaminants, ainsi que leurs sources, à l’échelle du continuum atmosphère – sol – rivière. Cette étude a donc pour objectif d’évaluer les variations temporelles et spatiales de deux types de contaminants historiques, les hydrocarbures aromatiques polycycliques (HAP) et certains éléments traces (ET), à l’échelle du bassin versant de l’Orge (950 km2), présentant une urbanisation croissante d’amont en aval. Plusieurs approches ont été utilisées pour tracer les transferts de particules en rivière (radionucléides ⁷Be, ²¹⁰Pb, ¹³⁷Cs), et déterminer les sources de Pb (isotopes du Pb), et les sources de HAP (rapports de molécules).Les résultats ont mis en évidence un impact important des zones urbaines sur la qualité de la rivière Orge en aval du bassin : contamination importante en métaux (Cu, Zn, Sb, Pb) et en HAP de la phase particulaire, et des niveaux élevés en SO42⁻, Na⁺ et Cl⁻, Cu, Zn et Pb dans la phase dissoute. Le traçage des sédiments par les radionucléides a permis d’observer un apport de particules provenant du ruissellement urbain en aval, et d’identifier les particules de route (ou Road Deposited Sediment) comme source principale. Les signatures isotopiques du Pb ainsi que les signatures en HAP permettent de confirmer que le ruissellement urbain est le principal vecteur de contamination. Les estimations des flux d’ET et HAP annuels et saisonniers entrants (retombées atmosphériques) et sortants (exportés par la rivière) ont mis en évidence une accumulation globale à l’échelle du bassin, qui comporte déjà un stock important de contaminants dans ses sols. Cette étude montre ainsi l’importance d’étudier la Zone Critique dans son ensemble afin d’évaluer la dynamique des contaminations au sein et entre ses différents compartiments, et met en évidence l’efficacité du couplage de plusieurs approches afin de comprendre le système entier. Ces résultats pourraient à terme permettre l’établissement d’un modèle de transfert de contaminations au sein d’un bassin urbain. / The development of human societies since the 19th century has led to deleterious impacts on the Critical Zone (from atmosphere to river, including biosphere and soils). Despite the decrease of pollutions since the late 1960’s, contaminations remain especially in urban environment, concentrating human activities. To better manage this pollution, it is necessary to understand the dynamics and pathways of contaminants through the atmosphere – soil – river continuum. The goal of this study in thus to evaluate the temporal and spatial variations of two contaminants (polycyclic aromatic hydrocarbons (PAH) and trace elements (TE)) in the Orge River catchment (900 km2, France) being under increasing urban pressure from up to downstream. Several fingerprinting approaches were used to trace sediment dynamics in the river (radionuclides: ⁷Be, ²¹⁰Pb, ¹³⁷Cs), to identify lead sources (lead isotopes) and PAH sources (PAH molecular ratios). The results demonstrated the strong influence of downstream urban areas on the river quality, with an increasing contamination for Cu, Zn, Sb, Pb and PAH in the particulate phase, and for SO42⁻, Na⁺ et Cl⁻, Cu, Zn and Pb in the dissolved phase. The sediment fingerprinting using radionuclides revealed a significant input of particles originating from urban areas and transferred through urban runoff, and identified road deposited sediments as the major source of contaminated particles downstream. Source tracking of Pb and PAH confirmed urban runoff as the main pathway of river contamination. In addition, annual and seasonal PAH and TE fluxes were estimated respectively for the atmospheric inputs, and riverine exports and revealed a global accumulation of contaminant over the catchment, already containing a significant stock of pollutants in its soils. Finally, this study highlights the need to integrate the Critical Zone and the potential of coupling multiples tracking approaches to properly evaluate the contaminant dynamics. These results may be used to establish a model of contaminants transfer in urban catchments.
310

Inomhuspositionering med bredbandig radio

Gustavsson, Oscar, Miksits, Adam January 2019 (has links)
In this report it is evaluated whether a higher dimensional fingerprint vector increases accuracy of an algorithm for indoor localisation. Many solutions use a Received Signal Strength Indicator (RSSI) to estimate a position. It was studied if the use of the Channel State Information (CSI), i.e. the channel’s frequency response, is beneficial for the accuracy.The localisation algorithm estimates the position of a new measurement by comparing it to previous measurements using k-Nearest Neighbour (k-NN) regression. The mean power was used as RSSI and 100 samples of the frequency response as CSI. Reduction of the dimension of the CSI vector with statistical moments and Principal Component Analysis (PCA) was tested. An improvement in accuracy could not be observed by using a higher dimensional fingerprint vector than RSSI. A standardised Euclidean or Mahalanobis distance measure in the k-NN algorithm seemed to perform better than Euclidean distance. Taking the logarithm of the frequency response samples before doing any calculation also seemed to improve accuracy. / I denna rapport utvärderas huruvida data av högre dimension ökar noggrannheten hos en algoritm för inomhuspositionering. Många lösningar använder en indikator för mottagen signalstyrka (RSSI) för att skatta en position. Det studerades studerade om användningen av kanalens fysikaliska tillstånd (CSI), det vill säga kanalens frekvenssvar, är fördelaktig för noggrannheten.Positioneringsalgoritmen skattar positionen för en ny mätning genom att jämföra den med tidigare mätningar med k-Nearest Neighbour (k-NN)-regression. Medeleffekten användes som RSSI och 100 sampel av frekvenssvaret som CSI. Reducering av CSI vektornsdimension med statistiska moment och Principalkomponentanalys(PCA) testades. En förbättring av noggrannheten kunde inte observeras genom att använda data med högre dimension än RSSI. Ett standardiserat Euklidiskt eller Mahalanobis avståndsåatt i k-NN-algoritmen verkade prestera bättre än Euklidiskt avstånd. Att ta logaritmen av frekvenssvarets sampel innan andra beräkningar gjordes verkade också förbättra noggrannheten.

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