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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.
511

Eco-labeling organizations and the credibility debate in International Relations

Stoyanova, Svetoslava January 2019 (has links)
The main purpose of this thesis is to explore the relationship between best practice adherence and the ownership status of an eco-labeling organization. The research question that is aiming to answer is what key factors most often explain differences in the level of credibility between for-profit carbon management eco-labels and not-for-profit carbon management eco-labels in transnational environmental governance. The case studies of interest are the two certification agencies Verra and The Carbon Reduction Institute. The issue of credibility of eco-labeling schemes will be looked through a Green IR theoretical perspective and debunked with Neoliberal IR theory. The methods which will be used are Small-N comparison and Qualitative Content Analysis conducted through Index for Best Practices. The data for the study is acquired from the online platforms of the two case studies for investigation.
512

Dynamique de la réplication chez l'archée Haloferax volcanii / Replication dynamics in the archaeon Haloferax volcanii

Collien, Yoann 14 October 2019 (has links)
Haloferax volcanii est une archée appartenant au phylum euryarchaeota et à la classe des Halobacteriales. Les mécanismes liés à la réplication et à la réparation chez les archées sont très similaires à ceux rencontrés chez les eucaryotes, faisant d’H. volcanii un des organismes modèle pour l’étude de la réplication et de la biologie des archées, notamment car de nombreux outils génétiques sont disponibles chez cet organisme. De plus, H. volcanii possède la particularité de pouvoir avoir toutes ses origines de réplication supprimées, soulevant beaucoup de questions sur les mécanismes impliqués. Plusieurs hypothèses ont été émises sur la façon dont cette souche initie sa réplication, basées soit sur la dérivation des mécanismes liés à la réparation de l’ADN, soit sur un mécanisme d’initiation de la réplication indépendant des origines. Afin d’étudier ces mécanismes liés à la réplication, j’ai construit une souche d’H. volcanii capable d’incorporer des analogues de la thymidine dans l’ADN lors de sa synthèse grâce à la délétion de gènes impliqués dans la voie de biosynthèse de la thymidine. Des temps de cultures courts de la souche en présence d’un analogue permet son incorporation au niveau des zones actives de réplication pour marquer spécifiquement l’ADN néosynthétisé. L’immunodétection de l’analogue incorporé à l’ADN, en travaillant en cellule entière avec un microscope à fluorescence, permet la localisation de l’ADN néosynthétisé, reflétant ainsi les régions où la réplication est active. Ces analyses révèlent majoritairement 2 à 3 régions de réplication actives dans des cellules en prolifération, sans localisation particulière. Ces régions ont déjà été observées en étudiant la localisation d’une protéine clé de la réplication (RPA2) fusionnée à la protéine verte fluorescente GFP, confirmant sa localisation aux zones actives de réplication. Une étonnante variabilité observée d’une cellule à l’autre et suggère une initiation probabiliste de la réplication. Il est également étonnant de n’observer qu’aussi peu de zones actives de réplication, comparé au fort taux de polyploïdie de cette souche. Se pose alors la question de ce à quoi correspondent ces zones de réplication. Pour cela, j’ai développé chez H. volcanii la technique de peignage moléculaire permettant d’isoler des molécules individuelles d’ADN et révéler spécifiquement les analogues incorporés pour pouvoir déterminer le nombre de copies du chromosome qui sont actives lors de la réplication, ainsi que le nombre d’origines actives sur chacune des copies. J’ai également développé une technique de Time-lapse dans le but de suivre ces régions au cours du temps en observant les divisions cellulaires directement sous le microscope. / Haloferax volcanii is an archaea belonging to the phylum euryarchaeota and the class Halobacteriales. The mechanisms related to replication and repair in archaea are very similar to those found in eukaryotes, making H. volcanii a relevant model organisms for the study of replication and archaeal biology, especially since many genetic tools are available. Interestingly, all replication origins can be removed from the chromosome of H. volcanii, raising many questions about the mechanisms involved. Several hypotheses have been proposed on how this strain initiates its replication, either relying on recombination-dependent replication initiation or an origin-independent mechanism. In order to study these replication-related mechanisms, I have constructed a strain of H. volcanii able to incorporate thymidine analogues into DNA during its synthesis by deleting genes involved in the thymidine biosynthesis pathway. A short-time cultures of the strain in the presence of an analogue allows its incorporation in nascent DNA. By immunodetection of the analog coupled to fluorescence microscopy observation of whole cells, it is possible to investigate the localization of neosynthesized DNA,which reflect the regions where replication is active. These analyses revealed mainly 2 to 3 active replication regions per cell, without any particular location. These regions had already been observed by studying the localization of a key replication protein (RPA2) fused to the fluorescent green protein GFP, confirming its location in active replication areas. A surprising variability in the number of replication foci from one cell to another was observed, suggesting a probabilistic initiation of replication. It is also surprising to observe so few active replication areas compared to the high polyploidy of this strain. This raises the question of what these replication areas correspond to. For further understanding, I developed for H. volcanii molecular combing, to isolate individual DNA molecules and specifically reveal incorporated analogues to determine the number of copies of the chromosome that are being replicated, as well as the number of active origins on each of the copies. I have also developed time-lapse approach to track these regions over time by monitoring cell proliferation directly under the microscope.
513

Flexible Structured Prediction in Natural Language Processing with Partially Annotated Corpora

Xiao Zhang (8776265) 29 April 2020 (has links)
<div>Structured prediction makes coherent decisions as structured objects to present the interrelations of these predicted variables. They have been widely used in many areas, such as bioinformatics, computer vision, speech recognition, and natural language processing. Machine Learning with reduced supervision aims to leverage the laborious and error-prone annotation effects and benefit the low-resource languages. In this dissertation we study structured prediction with reduced supervision for two sets of problems, sequence labeling and dependency parsing, both of which are representatives of structured prediction problems in NLP. We investigate three different approaches.</div><div> </div><div>The first approach is learning with modular architecture by task decomposition. By decomposing the labels into location sub-label and type sub-label, we designed neural modules to tackle these sub-labels respectively, with an additional module to infuse the information. The experiments on the benchmark datasets show the modular architecture outperforms existing models and can make use of partially labeled data together with fully labeled data to improve on the performance of using fully labeled data alone.</div><div><br></div><div>The second approach builds the neural CRF autoencoder (NCRFAE) model that combines a discriminative component and a generative component for semi-supervised sequence labeling. The model has a unified structure of shared parameters, using different loss functions for labeled and unlabeled data. We developed a variant of the EM algorithm for optimizing the model with tractable inference. The experiments on several languages in the POS tagging task show the model outperforms existing systems in both supervised and semi-supervised setup.</div><div><br></div><div>The third approach builds two models for semi-supervised dependency parsing, namely local autoencoding parser (LAP) and global autoencoding parser (GAP). LAP assumes the chain-structured sentence has a latent representation and uses this representation to construct the dependency tree, while GAP treats the dependency tree itself as a latent variable. Both models have unified structures for sentence with and without annotated parse tree. The experiments on several languages show both parsers can use unlabeled sentences to improve on the performance with labeled sentences alone, and LAP is faster while GAP outperforms existing models.</div>
514

A rotulagem de alérgenos alimentares em alimentos embalados análise da descrição, riscos e ambiguidades nos grupos da pirâmide alimentar brasileira. /

Lopes, Joice Ferreira January 2019 (has links)
Orientador: Nilton Carlos Machado / Resumo: Introdução. As alergias alimentares são um problema crescente no mundo, e a única maneira de tratar continua sendo a exclusão de alimentos com a proteína implicada. A ANVISA estabeleceu requisitos para a rotulagem dos principais alimentos que causam alergias alimentares. Portanto a leitura dos rótulos dos alimentos embalados deve ser praticada por todo cuidador de crianças alérgicas. Objetivo. Qualificar os rótulos apresentados pelas indústrias de alimentos com base na resolução atual e propor medidas que beneficiem a leitura de rótulos pelo público alérgico. Métodos. Estudo observacional transversal para avaliar a rotulagem de alérgenos de alimentos embalados. No primeiro momento foi realizada uma busca em supermercados de diferentes marcas de gêneros alimentícios. No segundo momento mediante sorteio eletrônico foi obtida amostra para analise, composta do mínimo de 50% de marcas de alimentos embalados de cada gênero alimentício. Posteriormente, foi realizada fotografia digital de cada produto, em todas as suas dimensões (painel principal, laterais e fundos). Os alimentos embalados foram divididos com base nos Grupos da Pirâmide alimentar brasileira. Foram analisados: os ingredientes presentes e as características da rotulagem. Dados apresentados de forma descritiva. A classificação dos rótulos foi apresentada em escore baseado na resolução vigente, gerando pontuação de 0 a 10 aos diferentes alimentos dos Grupos da Pirâmide alimentar brasileira. Resultados. Os alimentos embal... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction. Food allergies are a growing problem worldwide, and the only way to treat them is to exclude foods with the protein involved. ANVISA has established requirements for the labelling of major foods that cause food allergies. Therefore, the reading of packaged food labels should be practiced by all caregivers of allergic children. Aims. Qualify the labels presented by the food industries based on the current resolution and propose measures that benefit the reading of labels by the allergic public. Methods. Cross-sectional observational study to evaluate allergen labelling of packaged foods. At first, a search was done in supermarkets of different brands of foodstuffs. In the second moment, utilizing an electronic draw, a sample was obtained for analysis, composed of at least 50% of packaged food brands of each foodstuff. Subsequently, digital photography of each product was performed, in all its dimensions (main panel, sides and bottoms). The packaged foods were divided based on the Brazilian Food Pyramid Groups. Were analyzed: the present ingredients and the characteristics of the labelling. Data are presented descriptively. The classification of the labels was presented in a score based on the current resolution, generating a score from 0 to 10 to the different foods of the Brazilian Food Pyramid Groups. Results. Packaged foods have quality information, with labeling scores close to the maximum in all groups. Regarding the indication of the presence of allergens: ... (Complete abstract click electronic access below) / Mestre
515

Narkotikapolitisk debatt i svensk massmedia : "Sprickor i muren" / The Drug policy discussion in Swedish mass media : "Cracks In The Wall"

Nerf, Malin January 2020 (has links)
The aim of this study has been to analyze the current Swedish drug policy discussion in mass media. In the discussion several different dividing lines are drawn up which highlights different standpoints in the drug policy. The study's methodological starting point is qualitative text analysis and analysis from the third dimension which entails that the macrolevel perspective is in focus. The study's theoretical referens frame originates from the problemperspective and the labeling theory. The results are showing that the dividing lines in the discussion are about the different points of view; harm reduction or prohibition. This is connected to the current drug policy debate about a decriminalization and legalization, or if Sweden should continue to keep a prohibition drug policy. In the discussion decriminalization is presented as a solution which would open up for the insertion of new harm reduction strategies, while a prohibition politic is considered to have a preventative effect on the whole population. The drug problems are complex which in turn make them really be about socioeconomical factors, class distinctions, stigmatization and labeling. The conclusion is that we stand before a possible change, that would mean parting from the prohibiton drug policy that is very firmly cemented in our society. The topical drug policy discussion in mass media is dominated by participants that advocate a conversion of the current drug policy which could be seen as an indicator that change is forthcoming. However, at the same time there is unwillingness amongst leading politicians in Sweden to open up for transformation which could amount to the Swedish drug policy to continue to be as it is. / Syftet med denna studie har varit att analysera aktuell svensk narkotikapolitisk debatt i massmedia. I debatten dras ett antal skiljelinjer upp som markerar olika narkotikapolitiska ståndpunkter. Studiens metodologiska utgångspunkt är kvalitativ textanalys och analys ur tredje dimensionen, vilket innebär att makroperspektivet är i fokus. Studiens teoretiska referensram utgår från problemperspektiv och stämplingsteorin.  Resultatet visar på att skiljelinjerna i debatten markeras av de olika synsätten om skademinimering eller prohibition. Detta har ett samband med den pågående narkotikapolitiska diskussionen i massmedia om avkriminalisering och legalisering eller om Sverige ska fortsätta driva en repressiv narkotikapolitik. I den massmediala debatten framställs avkriminalisering som en lösning som skulle kunna öppna upp för införandet av nya skademinimerande insatser, medan en repressiv politik anses ha en preventiv effekt på befolkningen i helhet. Narkotikaproblematiken är komplex, vilket gör att problematiken egentligen tycks handla om socioekonomiska faktorer, klasskillnader, stämpling och stigma.  Slutsatsen är att vi står inför ett eventuellt skifte inom svensk narkotikapolitik, vilket skulle innebära ett avsteg från den repressiva narkotikapolitiken. Den aktuella narkotikapolitiska debatten i massmedia domineras av aktörer som förespråkar en förändring av nuvarande narkotikapolitik, detta skulle kunna ses som en indikator på att en förändring är på gång. Samtidigt finns det en ovillighet bland ledande politiker att öppna upp för en förändring, vilket likväl kan innebära att den svenska narkotikapolitiken fortsättningsvis kommer förbli oförändrad.
516

Eine Implementierung von Dungs abstrakten Argumentations-Frameworks

Tiepmar, Jochen 19 February 2018 (has links)
Abstrakt Argumentations – Frameworks ließen sich mithilfe der zur Verfügung gestellten Algorithmen zuverlässig und strukturiert implementieren. Die Möglichkeiten, welche die Objektorientierung bietet, ließen dabei eine Implementierung zu, welche dieses Modell unabhängig von seiner Umgebung gestaltet und gleichzeitig die Zusammenarbeit dieses Modells mit dieser Umgebung ermöglicht. Daher eignet sich das Programm als Möglichkeit der Visualisierung dieser Frameworks und liefert gleichzeitig ein unabhängiges Paket, mit dessen Hilfe sich die zugrunde liegenden Berechnungen zuverlässig durchführen lassen.
517

Part-based recognition of 3-D objects with application to shape modeling in hearing aid manufacturing

Zouhar, Alexander 14 August 2015 (has links)
In order to meet the needs of people with hearing loss today hearing aids are custom designed. Increasingly accurate 3-D scanning technology has contributed to the transition from conventional production scenarios to software based processes. Nonetheless, there is a tremendous amount of manual work involved to transform an input 3-D surface mesh of the outer ear into a final hearing aid shape. This manual work is often cumbersome and requires lots of experience which is why automatic solutions are of high practical relevance. This work is concerned with the recognition of 3-D surface meshes of ear implants. In particular we present a semantic part-labeling framework which significantly outperforms existing approaches for this task. We make at least three contributions which may also be found useful for other classes of 3-D meshes. Firstly, we validate the discriminative performance of several local descriptors and show that the majority of them performs poorly on our data except for 3-D shape contexts. The reason for this is that many local descriptor schemas are not rich enough to capture subtle variations in form of bends which is typical for organic shapes. Secondly, based on the observation that the left and the right outer ear of an individual look very similar we raised the question how similar the ear shapes among arbitrary individuals are? In this work, we define a notion of distance between ear shapes as building block of a non-parametric shape model of the ear to better handle the anatomical variability in ear implant labeling. Thirdly, we introduce a conditional random field model with a variety of label priors to facilitate the semantic part-labeling of 3-D meshes of ear implants. In particular we introduce the concept of a global parametric transition prior to enforce transition boundaries between adjacent object parts with an a priori known parametric form. In this way we were able to overcome the issue of inadequate geometric cues (e.g., ridges, bumps, concavities) as natural indicators for the presence of part boundaries. The last part of this work offers an outlook to possible extensions of our methods, in particular the development of 3-D descriptors that are fast to compute whilst at the same time rich enough to capture the characteristic differences between objects residing in the same class.
518

Influence of Humic Acids on the Migration Behavior of Radioactive and Non-Radioactive Substances Under Conditions Close to Nature -Synthesis, Radiometric Determination of Functional Groups, Complexation-: Influence of Humic Acids on the Migration Behavior of Radioactive and Non-Radioactive Substances Under Conditions Close to Nature -Synthesis, Radiometric Determination of Functional Groups, Complexation-

Nitsche, Heino, Heise, Karl-Heinz, Bernhard, Gert, Schmeide, Katja, Pompe, Susanne, Bubner, Marianne January 2000 (has links)
The interaction behavior of humic acids with uranium(VI) and the influence of humic substances on the migration behavior of uranium was investigated. A main focus of this work was the synthesis of four different humic acid model substances and their characterization and comparison to the natural humic acid from Aldrich. A radiometric method for the determination of humic acid functional groups was applied in addition to conventional methods for the determination of the functionality of humic acids. The humic acid model substances show functional and structural properties comparable to natural humic acids. Modified humic acids with blocked phenolic OH were synthesized to determine the influence of phenolic OH groups on the complexation behavior of humic acids. A synthesis method for 14C-labeled humic acids with high specific activity was developed. The complexation behavior of synthetic and natural humic acids with uranium(VI) was investigated by X-ray absorption spectroscopy, laser-induced fluorescence spectroscopy and FTIR spectroscopy. The synthetic model substances show an interaction behavior with uranium(VI) that is comparable to natural humic acids. This points to the fact that the synthetic humic acids simulate the functionality of their natural analogues very well. For the first time the influence of phenolic OH groups on the complexation behavior of humic acids was investigated by applying a modified humic acid with blocked phenolic OH groups. The formation of a uranyl hydroxy humate complex was identified by laserspectroscopic investigations of the complexation of Aldrich humic acid with uranium(VI)at pH 7. The migration behavior of uranium in a sandy aquifer system rich in humic substances was investigated in column experiments. A part of uranium migrates non-retarded through the sediment, bound to humic colloids. The uranium migration behavior is strongly influenced by the kinetically controlled interaction processes of uranium with the humic colloids. The influence of humic acids on the sorption of uranium(VI) onto phyllite was investigated in batch experiments using two different humic acids. The uranium(VI) sorption onto the rock phyllite is influenced by the pH-dependent sorption behavior of the humic acids.
519

Photoaffinity labeling the nucleotide sites of the sarcoplasmic reticulum Ca²⁺-ATPase

Seebregts, Christopher J January 1989 (has links)
We have synthesized a new class of photoaffinity analogs, 2',3'-O-(2,4,6-trinitrophenyl)-8-azido-ATP, -ADP and -AMP (TNP- 8N₃ATP, -ADP and -AMP), and their radiolabeled derivatives, and characterized their interaction with the sarcoplasmic reticulum Ca²⁺-ATPase. The TNP-8N₃-nucleotides were synthesized from ATP in three steps involving bromination in the 8-position of the adenine ring followed by displacement with an azido group and then trinitrophenylation of the resulting 8N₃-nucleotide with TNBS. Inclusion of the oxidizing agent, DTNB, in the final reaction was found to be necessary to prevent reduction of the azido group by the released sulfite anion and also elevated the yield of trinitrophenylation to about 80%. Purity was determined spectrophotometrically, as well as by anion exchange TLC and reversed phase HPLC. In the dark, the compounds were found to display most of the features of the parent TNP-nucleotides and interacted with the Ca²⁺-ATPase in a similar way. When activated by illumination, the probes were specifically incorporated into SR vesicles with high efficiency at alkaline pH. The site of labeling was identified as being on the A₁ tryptic fragment.
520

Is Hair Just Hair? : The Role of Hair in Identity Processes and Contestations of Black Women in Sweden

Therre, Daniel January 2022 (has links)
This bachelor thesis provides an analysis of hair and its role for the racial and ethnic identity of Black women living in Sweden. This is achieved by analyzing interviews with five women who reside in different urban areas throughout Sweden. In the analysis, the concept of Othering and social identity theory by Fiske and Taylor (2016) have been used to examine the position of the interviewees within Swedish society and the role of hair in their racial and ethnic identity. The results of the analysis show, that hair is a significant part of the interviewed women’s racial and ethnic identity. Furthermore, the results also show the ambivalence of hair for the women; though their hair is crucial for their self-identification and self-esteem, women are in a constant struggle with insecurities stemming from perceived external identification processes through negative labels attached to their hair.

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