Student Number : 0401422G - MSc dissertation - School of Chemical and Metallurgical Engineering - Faculty of Engineering / Mixing is an important operation that is carried out in food, paint, pharmaceutical and mineral processing industries. Ball mills are one of the many mixing vessels used in a mineral processing industry. During grinding, the mill’s efficiency depends on particle presentation to the grinding media and the adequate utilisation of the applied forces to effect breakage of particles (ore). Utilisation of applied forces is affected by how well particles and grinding media are mixed. The study of charge mixing is important as it affects the mill’s production rate and accelerates media wear, thus relevant to the cost reduction for the milling process. The kinetics of mixing in a batch ball mill were quantified both radially and axially. Experiments were conducted in a laboratory batch ball mill and two experimental programs were used to study the mixing process. Radial mixing of particles was observed to increase with increasing mill speed. For a mill used in this study, mixing of particles at Nc=90% took almost half the total time taken at Nc=75% to reach completion. A simplified mathematical model is presented, which can be used to predict the radial mixing of particles in a ball mill. Axial mixing of particles was observed to be affected by both the charge system used and segregation of particles from the grinding media. It took a minute for mixing to reach 80% completion for a mill used in the experiments. Mixing of particles was faster in a steel balls/plastic powders charge system than in a glass beads/quartz charge system. The distribution of particles in a batch mill was observed to vary along the axis of the mill. The centre of the mill was overfilled with particles, U>1, while the regions near the mill ends were underfilled, U<1. The opposite was true for the grinding media. The data reported was based on measurements of particle distribution along the mill as affected by different charge systems. The work presented in this thesis is a contribution to the continuing research on mixing of particles in ball mills.

Existe-t-il un au-delà de la castration ? Cette aporie que Freud nous a légué comme un point de butée infranchissable est le point de départ de ma thèse. Celle-ci consistera à étudier le concept de la castration et son lien inextricable avec le complexe d’OEdipe, à travers les oeuvres de Sigmund Freud, Jacques Lacan et Pierre Fedida. A l’appui de la clinique psychanalytique d’aujourd’hui, il s’agira de montrer comment la cure psychanalytique, et la position du psychanalyste, visent à introduire la castration. La castration, au coeur de la théorie psychanalytique, est le pivot de la vie psychique et est impliquée dans la formation des symptômes mais aussi de leur résolution. Cetravail tente d’articuler les oeuvres de trois auteurs majeurs de la psychanalyse, Freud, Lacan et Fedida, non pas pour les opposer ou les confondre mais pour mettre en perspective leur champ d’expérience, selon leur référentiel et leur style, desquels ressortiront notamment les notions de spaltung (division et clivage) et d’absence / Is there exist one beyond castration ? This aporia where Freud left us as an insuperable point is the starting point of my thesis. This one will consist in studying the concept of castration an its inextricable link with the OEdipus complex, through the writings of Sigmund Freud, Jacques Lacan and Pierre Fedida. In support of the psychoanaytical private clinic of today, it will be a question of showing how the psychoanalytical cure, and the position of the psychoanalyst, aim at introducing castration. Castration, at the core of psychoanalytic theory, is the pivot of psychic life and is implied in the formation of the symptoms but also in their resolution. This work tries to articulate works of three major authors of the psychoanalysis, Freud, Lacan and Fedida, not to oppose them or confuse them but to put in perspective their field of experience, according to their reference and their style, of which will notably arise the concepts of spaltung (division and splitting) and of absence.

Cette thèse s’inscrit dans le cadre applicatif général de l'analyse de cellules uniques. Afin d’améliorer la sélectivité du tri de cellules uniques, les équipes de FEMTO-ST proposent de contrôler en boucle fermée les trajectoires des cellules entemps réel pendant leur trajet dans les puces dédiées au tri. Dans ce cadre, mes travaux de thèse portent sur une méthode novatrice de détection en temps-réel de la position des cellules, directement intégrée aux puces et basée sur le principephysique de la mesure d'impédance.Lors du passage d’une cellule dans un microcanal, celle-ci vient modifier l’impédance mesurable entre des électrodes placées sur les bords du canal.Une méthode générique permettant de formuler les variations d'impédance en fonction de la position de la particule été proposée (modèledirect).Une méthode d'estimation de la position d’une particule reposant sur les mesures d’impédance a également été proposée (modèle inverse). Celle-ci exploite un filtre de Kalman étendu, permettant la fusion de données en provenance de plusieurspaires d'électrodes, et exploitant les informations disponibles telles que la distribution du bruit de mesure et le modèle dynamique de la particule.La validation de la méthode a été effectuée sur un banc expérimental qui a été développé lors de cette thèse et sur des simulations numériques.Ces travaux montrent la pertinence d’exploiter l’impédancemétrie pour construire un capteur de position de particules immergées dans un microcanal. Cette méthode est une alternative à l’utilisation de microscopes optiques et présente l’avantage d’une grande compacité. / This thesis is part of the general application framework of single cell analysis. In order to improve the selectivity of single cell sorting, FEMTO-ST teams propose to control in closed loop the trajectories of the cells in real time during their journey in the chips dedicated to sorting. In this context, my thesis work focuses on an innovative method for real-time detection of cell position, directly integrated into chips and based on the physical principle of impedance measurement.When a cell passes through a microchannel, it changes the measurable impedance between electrodes placed on the edges of the channel.A generic method for formulating impedance variations as a function of particle position has been proposed (direct model). A method for estimating the position of a particle based on impedance measurements has also been proposed (inverse model). It uses an extended Kalman filter, allowing data from several pairs ofelectrodes to be merged, and exploiting available information such as measurement noise distribution and particle dynamic model. The validation of the method was carried out on an experimental bench that was developed during this thesis and on numerical simulations.This work shows the relevance of using impedance measurement to build a position sensor for particles immersed in a microchannel. This method is an alternative to the use of optical microscopes and has the advantage of being very compact.

The aim of this work was to investigate how it is to move in hierarchy from crew to officer within the seafaring profession and how to be affected by this. How you are perceived by the crew when going from to represent a part of a system to represent a different part of the same system and if you are ready to assume the responsibilities of the new role entails? This is relevant and interesting as we will soon is facing at this transition. The work is based on a qualitative approach. The choice of this method gave the information needed for a perfect result. Interviews were conducted through personal meetings with active officers which also provided the opportunity to ask follow-up questions and the respondents were given the opportunity to share their experiences. The results showed that the transition from crew to command seems to be something individual from person to person but consistently has been the feeling that it is a major challenge of excitement and some nervousness. The largest portion prior to having been men from before is that it felt familiar with the safety procedures on board and to have a basic sense of security regarding departures and mooring, loading and unloading. Most felt that it was difficult to give orders to his old sailor colleagues but afterwards it felt more natural.

The Independent Practice During the last hundred years, the music industry has evolved with the record labels playing a central role. However, many argue that this situation is about to change as record sales have decreased during the last ten years. This imminent change in the music industry will not only affect the multinational record labels, but also the independent record labels.  As record sales have decreased during the last ten years, the number of members in the Swedish Independent Music Producers Association (SOM) has increased and the association now includes 300 independent record labels which are responsible for around 30 percent of the music being produced in Sweden. However, they can be considered a dominated group within the music industry, since they only have around 10 percent of the total market shares when it comes to selling figures. Considering the changes in record sales, the domination of the major record labels and the somewhat fascinating growth of independent actors during turbulent times, this thesis will study how the Swedish independent actors relate to the practices and ideals relevant in the daily work of running an independent record label. The practices studied in this thesis are the practice of work, the practice of recognition and the practice of content production. The purpose of this thesis is to analyse how independence is constructed among the members of SOM. The thesis is based on material collected in a web survey as well as seven interviews with representatives of indie labels. The web survey was distributed to all members of SOM, and the interviewed informants were selected by snowball sampling, using a locator to find informants. The survey material was analysed with cluster and variance analysis, while the interview material was analysed using content analysis – searching for themes connected to the practices. All material is understood through the theoretical frame of the field theory. The main results of the study are that there are different ways of relating to practices among the Swedish independent actors, and that these ways of relating are closely connected to their position within the field. There are common ways of relating to practices such as always promoting DIY, the importance of music and the need to resist the dominance of the major labels. However, the independent actors are not consistent in how these commonalities work in practice. For example, DIY is not applied if it is not economically necessary, and the need to resist the major labels is only apparent when the independent actor has a weaker position within the field. The more established an independent actor is within the field, the lesser resistant he is against the dominating structures of the music industry.  As a result of a weakening resistance against the major labels, the independent actors turn to struggle each other.

Socioekonomiska villkor under livsloppet påverkar ålderdomen på många olika sätt. Individer som haft en lägre socioekonomisk position löper bland annat en större risk att dö i förtid och drabbas av ohälsa. Syftet med studien är att studera människors livslopp med fokus på olika socioekonomiska villkor under uppväxt och livet fram till pensionen ur ett retrospektivt perspektiv. Kärnan i uppsatsen är att undersöka deltagarnas livslopp utifrån en historisk och individuell kontext och analysera hur den subjektiva upplevelsen av livskvalitet ser ut i ålderdomen. Studiens undersökningsdesign bygger på livsloppsintervjuer och kompletterande enkät. Deltagarna är födda under trettio och fyrtiotalet och samtliga är pensionärer. För att studera hur socioekonomiska villkor påverkar livet efter pensionen är det väsentligt att deltagarnas socioekonomiska positioner ser olika ut. Hälften av våra respondenter lever under sämre socioekonomiska villkor medan resterande har en mer fördelaktig social position i samhället. Uppsatsen tillämpar fem teoretiska perspektiv där alla har olika funktion i arbetets varierande delar. Teorierna tillsammans med internationell och nationell forskning har spelat en stor roll vid analysen av det insamlade materialet. Resultatet av studien visar att ett antal faktorer under livsloppet har påverkan på de äldres liv efter pensionen. Dessa faktorer är samhällelig och historisk kontext, socioekonomiska villkor under uppväxten, kön och klass. Upplevelsen av livskvalitet efter pensioneringen visar sig vara relativt lika hos samtliga respondenter.

Bakgrund: Cerebral syrebrist är ett problem som kan ge katastrofala konsekvenser även hos friska individer. Patienter som skall genomgå axeloperation i beach-chair position är en patientgrupp som har högre risk att drabbas av cerebral syrebrist (CDE). CDE är dock svårt att detektera med konventionell intraoperativ övervakning.Syfte: Att undersöka förekomst av CDE hos sövda patienter som genomgår axelkirurgi i beach-chair position samt att identifiera de specifika riskfaktorer för CDE och åtgärder som anestesisjuksköterskan kan utföra för att reducera dessa.Metod: Deskriptiv litteraturstudie med systematisk ansats.Resultat: Incidensen av uppmätta CDE varierade i de olika studierna mellan 3 % och 80 %. Anestesisjuksköterskan kan minska risk för CDE genom att preoperativt bedöma riskfaktorer i patientens anamnes samt intraoperativt genom blodtrycksreglering, ventilationsförändring, kontroll av beach-chair position samt kontroll av huvudets position.Slutsats: Genom att anestesisjuksköterskan uppmärksammar specifika riskfaktorer i patientens anamnes samt utför intraoperativa åtgärder som syftar till att säkerställa adekvat blodtryck och optimal syresättning kan risken för CDE minska. Mätning av cerebral syresättning med NIRS rekommenderas som ett komplement för att detektera förekomst av CDE. / Background: Cerebral desaturation is a problem, which may result in catastrophic consequences even with healthy individuals. Patients who will undergo shoulder surgery in beach-chair position are at higher risk to be affected by cerebral desaturation events (CDE). However, CDE is hard to detect with conventional intraoperative surveillance.Purpose: To investigate incidence of CDE with anesthetized patients undergoing shoulder surgery in beach-chair position, and to identify the specific risk factors and measures the nurse anesthetist may perform to reduce those.Method: Descriptive literature review with systematic approach.Result: The incidence of measured CDE varied between 3% and 80% in the different studies. The nurse anesthetist may reduce the risk for CDE by preoperatively assess the risk factors in the medical history of the patient and intraoperatively by regulation of the blood pressure, changes in ventilation, control of beach-chair position and control of the patients head position.Conclusion: By paying attention to specific risk factors in the patients medical history and performing intraoperative measures to ensure adequate blood pressure and optimal saturation the risk for CDE may be lowered. Measuring cerebral saturation with NIRS technology is recommended as a complement to be able to detect incidence of CDE.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 89-117).

Cette étude se penche sur le problème de l'occupation de la première et de l'avant-première positions dans des énoncés déclaratifs. Depuis Drach en 1937, on a en effet coutume de diviser l'énoncé allemand en champs. Ce travail s'appuiera sur un corpus (tome 2) composé d'exemples tirés aussi bien de la presse que de la littérature, le but étant de dégager des fonctions textuelles. Nous montrerons dans un premier temps qu'une différence syntaxique peut conduire à une différence sémantique. Puis nous présenterons un certain nombre d'expressions marquant le cadre énonciatif. Il sera enfin question de ce qu'il est convenu d'appeler la double occupation de la première position. L'ensemble des analyses se fera dans le cadre d'une analyse textuelle. / This case study looks into the specific case of the occupation of the prefield and pre-prefield position within a declarative utterance. Since Drach in 1937, the German utterance has often been divided into fields. This case will be composed of a corpus (tome 2) made up of examples from the press as well as from literary works and its purpose is to bring out textual functions. We will first demonstrate that a syntactic difference may lead to a semantic one. We will then present a certain number of phrases which are part of the enunciative framework. Finally, we will tackle what is commonly called the double occupation of the prefield. All the analyses will be performed through a textual analysis.

La position des membres le long du corps est reproductible chez une même espèce mais est très variable entre différentes espèces. Comment les membres acquièrent leur position et quel mécanisme est à l'origine de ces variations est à ce jour non élucidé. De part leur rôle dans la mise en place des axes embryonnaires, les gènes Hox sont depuis longtemps suspectés de jouer un rôle dans ce processus. Cependant les différentes preuves disponibles à ce jour restent indirectes et corrélatives. Chez l'embryon de poulet, je montre que la position des membres est établit précocement au cours du développement, lors de la gastrulation. Je démontre que la formation de la lame latérale (i.e. le tissue d'origine des membres) est un processus graduel et que l'activation séquentielle des gènes Hox spécifie ce tissue en domaines du membre et du flanc. Dans un second temps, une combinaison d'actions activatrice et répressive des gènes Hox sur le programme d'initiation du membre, actions liées à leur organisation colinéaire, est critique pour l'organisation de la lame latérale en domaines du membre et du flanc. Enfin, en étudiant des embryons de différentes espèces d'oiseaux présentant des variations dans la longueur de leur cou et donc dans la position de leur ailes (le poulet, l'autruche et le diamant mandarin), je montre que des changements relatifs dans la séquence d'activation colinéaire des gènes Hox au cours de la gastrulation sous-tendent les variations naturelles de la position de l'aile. L'ensemble de ces résultats montre que les gènes Hox jouent un rôle direct et précoce dans le positionnement des membres et propose un model général de mise en place d'un organisme par ces gènes. / Limb position along the main body axis is highly consistent within one species but very variable among tetrapods. Despite major advances in our understanding of limb patterning in three dimensions, how limbs reproducibly form along the anteroposterior axis remains largely unknown. Hox genes have long been suspected to play a role in this process, however supporting evidences are mostly correlative and a direct role has yet to be demonstrated. Here, using bird embryos, I show that limb position is established very early during development, during the process of gastrulation. I find that the formation of the Lateral Plate Mesoderm (i.e. the embryonic compartment from which limbs will form) is a progressive process and that co-linear activation of Hox genes sequentially patterns it along the antero-posterior axis. Subsequent combinatorial activation and repression activities of Hox genes on limb initiation are particularly critical to pattern the LPM into limb- and non-limb-forming domains. Finally, by analyzing chicken, zebra finch and ostrich embryos which exhibit variation in their forelimb position, I show that relative changes in the timing of co-linear Hox gene activation during gastrulation underlie variation in limb position. Altogether these result shed light on the cellular and molecular mechanism that regulate limb position by showing a direct and early role for Hox genes in this process during gastrulation and provide a mechanism for variation in body plan organization observed in tetrapods.