Thèses : « Dynamic segregation »

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Dubois, Florent. « Dynamic models of segregation ». Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0313.

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Cette thèse étudie les causes et conséquences du processus de ségrégation résidentielle dans l’Afrique du Sud (AFS) post-Apartheid. Nous nous intéressons à plusieurs aspects encore débattus dans la littérature. Le premier concerne l’impact des préférences des individus pour la composition raciale de leur voisinage sur la ségrégation. Le second a trait à l’impact de la ségrégation résidentielle sur les niveaux de revenus des différents groupes raciaux. Le dernier quantifie les différentes causes de la ségrégation. Dans le premier chapitre, nous réconcilions la littérature théorique sur l’impact des préférences pour la composition raciale du voisinage avec les observations empiriques de niveaux décroissants de ségrégation aux US et en AFS. Nous soutenons l’idée que si les individus internalisent les apports économiques et sociaux de chaque nouvel arrivant dans leur voisinage alors des voisinages intégrés peuvent émerger. Cet effet est empiriquement plus fort que l’homophilie et le racisme. Dans le second chapitre, nous étudions l’impact de la ségrégation sur l’ensemble de la distribution des revenus. Nous montrons que la ségrégation a un effet positif sur les hauts revenus pour les Blancs tandis qu’elle a un effet négatif pour les Noirs au bas de la distribution. L’effet de la ségrégation est souvent plus important que l’effet de l’éducation. Enfin, dans le troisième chapitre, nous quantifions l’impact de chaque déterminant de la ségrégation. Nous trouvons que le manque d’accès aux services publics de base est le déterminant principal, alors que les différences de caractéristiques sociodémographiques ne comptent que pour une faible part pour les quartiers les plus ségrégués
This thesis studies the causes and consequences of the residential segregation process in the post-Apartheid South Africa.Inside this general issue, we are interested in several aspects still debated in the literature on residential segregation. Thefirst concerns the impact of individuals’ preferences for the racial composition of their neighborhood on the segregationlevels. The second question deals with the impact of residential segregation on the income levels of each racial group. Thelast issue is related to quantifying the different causes of segregation.Three chapters constitute this thesis. In the first chapter, we reconcile the theoretical literature on the impact of preferencesfor the racial composition of the neighborhood with the empirical evidences of declining levels of segregation in theUnited-States and South Africa. We argue that if individuals internalize the economic and social life that a new entrantbrings with him, then integrated neighborhoods can emerge. This effect is empirically stronger than homophilly andracism. In the second chapter, we study the impact of residential segregation on the whole income distribution. We showthat residential segregation has a positif effect on top incomes for Whites, whereas it has a negatif effect for Blacks at thebottom of the distribution. The effect of residential segregation is even more important than the effect of education inmost cases. In the third chapter, we quantify the impact of each determinant of segregation. We find that the lackof access to basic public services is the main determinant, whereas differences in sociodemographics only account for asmall part in the most segregated areas

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Kastyak, Beata Maria. « Applying Schelling's dynamic models of segregation to psychological decision making ». Thesis, University of Leicester, 2015. http://hdl.handle.net/2381/32350.

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Agent-Based Models (ABM) have become accepted as an experimental technique in social psychology research. However, ABMs are rarely validated externally. This research attempted to experimentally validate, in particular the Schelling’s Dynamic Models of segregation. This model is an agent-based proximity model implemented with a new parameter, the tolerance level, which is based on perceived similarities of the agents. The introduction of this new parameter has made ABM applicable to social sciences. Five parameters (tolerance threshold, neighbourhood ranges, environment types, group size and proportions) of the model have been chosen to be tested experimentally and evaluated theoretically. Therefore, relevant chapters include an experimental and a theoretical section. In the experimental part group of participants played the linear public good game with altruistic punishment. The level of cooperation was measured through contributions scores. In the theoretical part the outcome of the simulation models was evaluated using the segregation factor. The experimental results and the simulation outcomes have been compared in each chapter separately. Five chapters inspected the five parameters of the Schelling model considering additional prospects. The tolerance threshold was tested using groups with different wealth origin. The neighbourhood ranges were tested using groups with different geographical proximities. The environment type parameter was tested using different gender groups. The group sizes parameter was tested using different community sizes. Finally the group proportions were tested by allocating the participants into groups with different ethnicity proportions. Additionally, the effects of these conditions were examined on altruistic punishment. The findings show that the contributions scores alter between the different scenarios. However, altruistic punishment is not always influenced. This thesis provides a partial validation of five parameters of the Schelling model and contributes to an effective development of all future ABMs. The research suggests unique recommendations for further research in both the experimental and theoretical parts.

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Makin, Simon J. « The role of static and dynamic fâ‚€ differences in concurrent vowel segregation ». Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434481.

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Fabig, Gunar. « Dynamic and ultrastructural characterization of chromosome segregation in C. elegans male meiosis ». Technische Universität Dresden, 2018. https://tud.qucosa.de/id/qucosa%3A32727.

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The production of germ cells is an essential process in all sexually reproducing eukaryotes. During male meiosis, four haploid sperm cells are formed from one primary spermatocyte, thereby undergoing two consecutive cell divisions after only one round of chromosome duplication. This process was studied in the nematode Caenorhabditis elegans, as this model organism offers a number of experimental advantages to simultaneously analyze spindle dynamics and ultrastructure. The worm is easy to cultivate, completely sequenced and numerous mutants are available, the worm is small and thus ideal for light and electron microscopic investigations, and the transparent body allows live-cell imaging within living animals. Importantly, meiotic spindles in C. elegans males are organized by centrosomes and show a lagging X-chromosome, which is always segregated after the autosomes have been partitioned to the newly forming secondary spermatocytes. The aim of this thesis was to systematically investigate this characteristic feature of chromosome segregation in male meiotic spindles. For that, spindle dynamics in the first and second meiotic division was analyzed with fluorescence light microscopy. Furthermore, the spindle ultrastructure was investigated in spindles of various stages of meiosis I using electron tomography. Light microscopy revealed a shortening of the distance between centrosomes and chromosomes (anaphase A) and an increase in the pole-to-pole distance (anaphase B). Moreover, spindles in male meiosis I and II showed differences in certain aspects of spindle dynamics. In addition it was demonstrated that spindles in metaphase II in the presence of a single X-chromosome were shorter compared to spindles without the X-chromosome. In addition, it was found that the process of aging had an impact on spindle length in both metaphase I and II. By manipulating the number of unpaired chromosomes, it could be demonstrated that the lagging behavior of univalent chromosomes is caused by the incapability of pairing in meiotic prophase. After performing a quantitative analysis of the light microscopic data it was further shown that a dynamic microtubule bundle is connecting the X-chromosome to the spindle poles. Using laser microsurgery it could be demonstrated that this bundle exerts a pulling force to the univalent chromosome throughout anaphase. Unexpectedly, electron tomography showed that anaphase-type movements of the autosomes were not accompanied by a shortening of the kinetochore microtubules. Instead, three findings indicated a shortening of the centrosome-chromosome distance itself: (1) upon anaphase onset, tension is released on the beforehand stretched autosomes; (2) centrosomes shrink in preparation for meiosis II and (3) the attachment angle of end-on microtubules changes. Interestingly, microtubules connecting the X-chromosome to the spindle poles showed a high curvature around the kinetochore region of the X-chromosome, suggesting an involvement of motor proteins in the process of segregation. Taken together, this thesis gives the first detailed quantitative analysis of spindle dynamics and architecture during male meiosis in the nematode C. elegans. This wild-type data will serve as a basis for future mutant analyses and should help to further understand the complex dynamic and ultrastructural aspects of spindle organization in the meiotic divisions in C. elegans males.

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Waheed, Qaiser. « Molecular Dynamic Simulations of Biological Membranes ». Doctoral thesis, KTH, Teoretisk biologisk fysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102268.

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Biological membranes mainly constituent lipid molecules along with some proteins and steroles. The properties of the pure lipid bilayers as well as in the presence of other constituents (in case of two or three component systems) are very important to be studied carefully to model these systems and compare them with the realistic systems. Molecular dynamic simulations provide a good opportunity to model such systems and to study them at microscopic level where experiments fail to do. In this thesis we study the structural and dynamic properties of the pure phospholipid bilayers and the phase behavior of phospholipid bilayers when other constituents are present in them. Material and structural properties like area per lipid and area compressibility of the phospholipids show a big scatter in experiments. These properties are studied for different system sizes and it was found that the increasing undulations in large systems effect these properties. A correction was applied to area per lipid and area compressibility using the Helfrich theory in Fourier space. Other structural properties like order of the lipid chains, electron density and radial distribution functions are calculated which give the structure of the lipid bilayer along the normal and in the lateral direction. These properties are compared to the X-ray and neutron scattering experiments after Fourier transform. Thermodynamic properties like heat capacity and heat of melting are also calculated from derivatives of energies available in molecular dynamics. Heat capacity on the other hand include quantum effect and are corrected for that by applying quantum correction using normal mode analysis for a simple as well as ambiguous system like water. Here it is done for SPC/E water model. The purpose of this study is to further apply the quantum corrections on macromolecules like lipids by using this technique. Furthermore the phase behavior of two component systems (phospholipids/cholesterol) is also studied. Phase transition in these systems is observed at different cholesterol concentrations as a function of temperature by looking at different quantities (as an order parameter) like the order of chains, area per molecule and partial specific area. Radial distribution functions are used to look at the in plane structure for different phases having a different lateral or positional order. Adding more cholesterol orders the lipid chains changing a liquid disordered system into a liquid ordered one and turning a solid ordered system into a liquid ordered one. Further more the free energy of domain formation is calculated to investigate the two phasecoexistence in binary systems. Free energy contains two terms. One is bulk freeenergy which was calculated by the chemical potential of cholesterol moleculein a homogeneous system which is favorable for segregation. Second is thefree energy of having an interface which is calculated from the line tension of the interface of two systems with different cholesterol concentration which in unfavorable for domain formation. The size of the domains calculated from these two contributions to the free energy gives the domains of a few nm in size. Though we could not find any such domains by directly looking at our simulations.

QC 20120913

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Choi, Sung Hugh. « The Role of Dynamic Cdk1 Phosphorylation in Chromosome Segregation in Schizosaccharomyces pombe : A Dissertation ». eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/453.

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The proper transmission of genetic materials into progeny cells is crucial for maintenance of genetic integrity in eukaryotes and fundamental for reproduction of organisms. To achieve this goal, chromosomes must be attached to microtubules emanating from opposite poles in a bi-oriented manner at metaphase, and then should be separated equally through proper spindle elongation in anaphase. Failure to do so leads to aneuploidy, which is often associated with cancer. Despite the presence of a safety device called the spindle assembly checkpoint (SAC) to monitor chromosome bi-orientation, mammalian cells frequently possess merotelic kinetochore orientation, in which a single kinetochore binds microtubules emanating from both poles. Merotelically attached kinetochores escape from the surveillance mechanism of the SAC and when cells proceed to anaphase cause lagging chromosomes, which are a leading cause of aneuploidy in mammalian tissue cultured cells. The fission yeast monopolin complex functions in prevention of mal-orientation of kinetochores including merotelic attachments during mitosis. Despite the known importance of Cdk1 activity during mitosis, it has been unclear how oscillations in Cdk1 activity drive the dramatic changes in chromosome behavior and spindle dynamics that occur at the metaphase/anaphase transition. In two separate studies, we show how dynamic Cdk1 phosphorylation regulates chromosome segregation. First, we demonstrate that sequential phosphorylation and dephosphorylation of monopolin by Cdk1 and Cdc14 phosphatase respectively helps ensure the orderly execution of two discrete steps in mitosis, namely sister kinetochore bi-orientation at metaphase and spindle elongation in anaphase. Second, we show that elevated Cdk1 activity is crucial for correction of merotelic kinetochores produced in monopolin and heterochromatin mutants.

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Furtado, Bernardo Alves. « Modeling social heterogeneity, neighborhoods and local influences on urban estate prices : spatial dynamic analyses in the Belo Horizonte metropolitan area, Brazil / ». Utrecht : Koninklijk Nederlands Aardrijskundig Genootschap [u.a.], 2009. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=018618333&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Fabig, Gunar [Verfasser], Michael [Gutachter] Göttfert et Diana [Gutachter] Chu. « Dynamic and ultrastructural characterization of chromosome segregation in C. elegans male meiosis / Gunar Fabig ; Gutachter : Michael Göttfert, Diana Chu ». Dresden : Technische Universität Dresden, 2019. http://d-nb.info/1226896804/34.

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Liu, Qingsong. « The Role of Mobility in the Socio-spatial Segregation Assessment with Social Media Data ». Kent State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=kent1618913543377221.

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Titos, Vivancos Iris 1986. « Topoisomerase II and dynamic microtubules solve sister chromatid intertwinings in anaphase ». Doctoral thesis, Universitat Pompeu Fabra, 2013. http://hdl.handle.net/10803/287225.

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At the metaphase-to-anaphase transition, spindle microtubules pull replicated chromosomes to the daughter cells, but full separation of long chromosome arms is achieved in late anaphase. We have created an allelic series of long chromosomes to elucidate the mechanisms involved in long chromosome resolution during mitosis. With this method we have shown that long chromosome cells are sensitized to the loss of genes involved in chromosome structure and segregation. We have discovered that Topoisomerase II is needed during anaphase to resolve distal regions of long chromosomes and that the activity of the microtubule polymerase Stu2 is crucial in the resolution of catenations. Moreover, we have identified the nuclear organization as a new source that contributes to the topological stress accumulated in chromosomes. Thus, topological constraints imposed by chromosome length and nuclear architecture determine the amount of sister chromatid intertwinings that must be resolved by Topoisomerase II and dynamic microtubules during anaphase.
A la transició entre metafase i anafase els microtúbuls del fus mitòtic transporten els cromosomes a les cèl·lules filles, tot i això la separació completa dels braços dels cromosomes no succeeix fins al final dʼanafase. Amb lʼobjectiu dʼentendre com es resolen els cromosomes llargs durant anafase, hem creat una sèrie al·lèlica de cromosomes artificalment llargs. Amb aquesta metodologia hem demostrat que les cèl·lules que contenen cromosomes llargs estan sensibilitzades a la pèrdua de gens involucrats en lʼestructura i la segregació de cromosomes. Hem descobert que la Topoisomerasa II es necesària durant anafase per resoldre les regions distals de cromosomes llargs i que lʼactivitat de la polimerasa de microtúbuls, Stu2, és essencial en la resolució de concatenacions entre cromàtides germanes. A més, hem pogut identificar lʼorganització nuclear com una nova font que contribueix a lʼestrés topològic acumulat als cromosomes. En conclusió, les restriccions topològiques que imposen tant la longitud dels cromosomes com lʼarquitectura nuclear determinen la quantitat de concatenacions entre cromàtides germanes que han de ser resoltes per la Topoisomerasa II i els microtúbuls dinàmics durant anafase.

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Haener, Edgar. « Microfluidic segregation of capsules ». Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/microfluidic-segregation-of-capsules(a7e001f1-536c-475d-83d5-82aaa4098f5b).html.

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This thesis investigates the transport and sorting of capsules (elastic membranes enclosing a liquid core) using viscous flow in complex vessel geometries. Of particular interest is passive sorting by deformability using only the fluid-structure interaction between the capsule, the viscous fluid and the geometry of the vessel. Millimetric alginate-ovalbumin capsules in the regime of negligible fluid inertia are used in this work. In order to characterise the elastic properties of the capsules, a novel numerical finite element model of the compression of a thick-shelled capsule between parallel plates is implemented. The constitutive model of the capsule membranes was determined by comparison to experimental data: a Yeoh constitutive model with the ratio of constants $C_1 = 1$, $C_2 = 0$ and $C_3 = 10$ describes the capsules used. Three geometries are investigated in this work. (i) A T-Junction bifurcation. Capsule deformation in the T-Junction bifurcation is characterised by the maximal length of the capsule $L_{max}$ and depends on the ratio of viscous to elastic forces, the capillary number $Ca$. The maximal length, $L_{max}$, is especially sensitive at distinguishing soft capsules by their deformability. The sensitivity of $L_{max}$ to capsule compliance and the large deformations that can be achieved makes the T-junction a promising geometry in which to measure elastic properties of the capsules. The rate of relaxation of the capsules after the bifurcation is independent of their deformation. (ii) A half-cylinder obstacle in a channel followed by a sudden expansion. We show that the half-cylinder obstacle causes capsule trajectories to vary depending on deformability. Capsules with a factor of three difference in deformability can be separated. A practical feature of the system is its relative insensitivity to the initial lateral position of the capsules in the channel. However, while the results are reproducible across different capsules, the variations in final position amount to 10 \% at fixed parameters. As these experiments were conducted with the same capsule under identical flow conditions, this is likely to represent the best case scenario. (iii) We adapt the pinched flow fractionation (PFF) geometry to the sorting of capsules. We show that the standard PFF device cannot be used to sort capsules. However, a novel mode of operation, termed the ``T-Junction'' mode, shows great promise for the sorting of capsules. The PFF device in the T-Junction mode separates capsules with a factor of 1.5 difference in deformability. This is twice as sensitive as the half-cylinder device, although larger variability was observed in the PFF device.

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Rmili, Yosra. « ÉTUDE DE LA DILATANCE DE REYNOLDS DU BÉTON ET DE SON EFFET SUR LA FORMATION DE LA COUCHE DE LUBRIFICATION DANS LES TUYAUX DE POMPAGE ». Electronic Thesis or Diss., CY Cergy Paris Université, 2024. http://www.theses.fr/2024CYUN1283.

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Le processus de pompage du béton revêt une importance capitale dans le secteur de construction, facilitant le transport du béton frais vers le site de coulée, voire des zones difficiles d'accès. Cette technique offre la possibilité d'atteindre des hauteurs et des distances considérables. Toutefois, ce processus n'est pas sans défis. Il est donc primordial de pouvoir bien prédire la pompabilité du béton. En effet, la pompabilité du béton dépend étroitement de ses propriétés rhéologiques et de sa capacité à former une couche de lubrification (CL) lors de son écoulement dans les conduites de pompage. Par conséquent, une bonne compréhension de la rhéologie du béton et des caractéristiques de la CL est essentielle, d'autant plus que les mécanismes de formation de cette dernière demeurent encore méconnus. Cette thèse se concentre sur l'étude de la dilatance de Reynolds (DR) en tant que mécanisme potentiel intervenant dans la formation de la CL, et elle vise à mettre en évidence les principaux paramètres qui les régissent. La première partie de l'étude présente le développement d'une nouvelle méthode pour évaluer les variations de volume induites par le cisaillement, nommée la dilatance de Reynolds du béton en écoulement à surface libre. Cette méthode, bien que plus fiable pour les bétons conventionnels, ne permet cependant pas d'explorer pleinement ce mécanisme. En conséquence, un nouveau dispositif empirique, le CRD-Test, a été conçu pour évaluer la dilatance de Reynolds des bétons autoplaçants soumis à différents scénarios de cisaillement à surface libre et sous pression, simulant ainsi les processus réels de coulage et de pompage. Dans cette seconde partie de l'étude, le béton autoplaçant (BAP) est considéré comme un mélange biphasique, composé de gros granulats (> 1,25 mm) immergés dans une matrice fluide de mortier fin (< 1,25 mm). En outre, le CRD-Test offre une couverture large des niveaux de cisaillement et de pression. Il repose sur un tribomètre à cylindre coaxial modifié, dont la vitesse de rotation varie de 0 à 3 tr/s, et sur un régulateur de pression d'air ajustable de 0 à 300 kPa. Le phénomène de dilatance de Reynolds se traduit par des fluctuations de la pression latérale mesurée au niveau du cylindre extérieur de cet appareil et a été étudié à travers de nouveaux indices. Les résultats expérimentaux révèlent que les indices de pression induits par la dilatance de Reynolds sont en accord avec la maniabilité du béton et ses paramètres de formulation. Les bétons autoplaçants présentant des faibles valeurs d'étalement montrent des indices de dilatance de Reynolds élevés sous cisaillement à surface libre et sous pression. De plus, une approche diphasique permet de mettre en évidence des corrélations entre la dilatance de Reynolds et les caractéristiques des granulats dont le diamètre est supérieur à 1,25 mm ainsi que les caractéristiques viscoplastiques du mortier fin, (i.e. la phase suspendante). De plus l'étude montre que la dilatance de Reynolds est principalement affectée par le degré d'empilement initial du squelette granulaire pendant le processus de pompage. Enfin, les valeurs de dilatance de Reynolds sont en en bon accord avec les caractéristiques du régime d'écoulement, la dynamique des particules et les indices de migration des particules sous l'effet du cisaillement. Selon les corrélations établies, il apparaît que la ségrégation dynamique peut significativement influencer les mécanismes de formation de la CL lors du pompage du béton à faibles taux de cisaillement, illustrant ainsi l'importance de la dilatance de Reynolds dans ce processus. Cependant, il a été observé qu'à des taux de cisaillement plus élevés, la ségrégation dynamique peut avoir un impact négatif sur les valeurs de dilatance de Reynolds, augmentant ainsi le risque de blocage durant le processus de pompage du béton
Concrete pumping process is important in the construction sector, facilitating the transport of fresh concrete to the casting site, even in difficult-to-access areas. This technique enables the achievement of considerable heights and distances. However, this process presents challenges. Therefore, accurately predicting the pumpability of concrete appears to be essential. Indeed, concrete pumpability relies on its rheological properties and its ability to form a lubrication layer (LL) during its flow through pipes. Accordingly, it is worthy to mention that mastering the rheology of concrete and understanding the characteristics of the LL is important, especially considering that the mechanisms of LL formation remain not well understood.This project focuses on investigating Reynolds dilatancy (RD), a potential mechanism involved in LL formation, and aims to highlight the key parameters governing it. The first part of the study introduces the development of a new method to assess shear-induced variations (RD) at free-surface flow. This method, although more reliable for conventional vibrated concrete (CVC), it does not fully explore this mechanism. Consequently, a new empirical device, the CRD-Test, was designed to evaluate the RD of self-compacting concrete (SCC) subjected to various scenarios under free-surface and pressurized conditions, simulating real casting and pumping processes. In this second part of the study, SCC is considered as a biphasic mixture of coarser particles (> 1.25 mm) in a fluid matrix of fine mortar (< 1.25 mm). Moreover, the new experimental device, named CRD-Test, offers wide range of shear and pressure levels. It is based on a modified coaxial cylinder tribometer, with a rotational speed ranging from 0 to 3 rps, and an air pressure regulator from 0 to 300 kPa. The RD phenomenon is manifested by fluctuations in lateral pressure measured at the outer cylinder of this apparatus and it was investigated through new indices.Experimental results reveal that RD values were found to be in good agreement with the workability and design parameters of the investigated concrete mixtures. Concrete with low fluidity values exhibited high RD indices under both free-surface and pressurized shear conditions. Furthermore, a biphasic approach highlights correlations between RD and the characteristics of aggregates with a diameter greater than 1.25 mm, as well as the viscoplastic characteristics of the fine mortar (i.e., the suspending phase). Moreover, RD results are mainly affected by the relative packing density of coarse aggregate during pumping process. Finally, Reynold values were in good agreement with flow regime characteristics, particle dynamics, and shear-induced particle migration indices. According to established correlations, dynamic segregation can significantly influence the mechanisms of LL formation during concrete pumping at low shear rates, illustrating the importance of Reynolds dilatancy in this process. However, at higher shear rates, dynamic segregation has been observed to negatively impact RD values, thereby increasing the risk of blockage during concrete pumping

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Bråmå, Åsa. « Studies in the Dynamics of Residential Segregation ». Doctoral thesis, Uppsala University, Institute for Housing and Urban Research, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6336.

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In four scientific papers, this thesis investigates the processes, in terms of movements of individuals, that have produced, reproduced and transformed patterns of residential segregation in Swedish cities between 1990 and 2000.

Paper 1 examines processes of immigrant concentration, and the role of the Swedish majority population in these processes. Neighbourhood transition and mobility are described and analysed for a selection of residential areas that have experienced increased immigrant concentration. The results show that low in-migration rate among Swedes, rather than high out-migration rate, has been the main driving force behind the production and reproduction of immigrant concentration areas.

Paper 2 investigates the hypothesis that distressed neighbourhoods retain their character of distress through selective migration. The socio-economic situations of in-migrants, out-migrants and stayers in the distressed neighbourhoods of Stockholm are analysed and compared, and the results show the hypothesis to be confirmed. The people who move in are more likely to be unemployed and dependent on social benefits, and have on average lower incomes than those who move out and those who remain in the neighbourhoods.

Paper 3 further investigates the selective character of the out-migration from distressed neighbourhoods. One important conclusion is that the out-migration flow from the distressed residential areas is socio-economically and ethnically selective. When demographic and socio-economic differences are controlled for, the likelihood of leaving the distressed neighbourhoods is much lower for an immigrant than for a Swedish-born person.

Paper 4 examines the migration flows of a whole city, Göteborg. The paper deals with some of the most common questions within segregation research; the degree of spatial concentration of different ethnic groups, processes of concentration and dispersal, the role of the minority enclaves as ports of entry to the local housing market, and how this differs between ethnic groups.

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Bråmå, Åsa. « Studies in the dynamics of residential segregation / ». Uppsala : Department of Social and Economic Geography, Uppsala University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6336.

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Reyes, Rodrigo. « Replisome Dynamics ans Chromosome Segregation in Escherichia Coli ». Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490350.

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Replication of the chromosome of E. coli starts at a single point and proceeds bidirectionally until the replication forks meet at the opposite side of the DNA molecule. All this occurs on a compacted (around 1000-fold) chromosomal DNA, which is also organized in a manner that reflects the genetic position of the loci. Any roles that DNA replication plays in helping segregate the new DNA molecules, and how replication relates to nucleoid organization, remain to be understood.

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Arsenault, Serge A. « The dynamics of texture segregation : a task comparison approach ». Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69546.

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The time course of texture segregation was studied for three different measures of segregation (detection, localization and identification of an embedded texture region) under three different raster width conditions (26$ sp prime$, 43$ sp prime$ and 61$ sp prime$ of arc) by using a backward masking paradigm. The masking data were described with an exponential model the parameters of which represent rate of performance improvement and asymptotic performance level. The results indicate that: (1) information supporting localization accrues more rapidly than information supporting identification, (2) increasing element spacing had a more detrimental effect on identification than on localization, (3) under most spacing conditions, performance on detection fell between that for localization and identification. In conclusion, these three widely used texture segregation tasks cannot be considered equivalent measures of a single process. However, comparisons among their respective time courses may enable us to better characterize the mechanisms underlying the segregation process.

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Fan, Jianmiao. « Simulated chromosome segregation and Min protein dynamics in Escherichia coli ». [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3301351.

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Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2007.
Title from dissertation home page (viewed Sept. 29, 2008). Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 0773. Adviser: Peter J. Ortoleva.

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Abdou, Mohamed A. « Determinants and dynamics of social and workplace segregation : a simulation study ». Thesis, University of Surrey, 2009. http://epubs.surrey.ac.uk/843429/.

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Segregation in workplaces and individuals' social networks based on ethnicity, race, and/or religion may have serious social and economic consequences. The relationship between social segregation and workplace segregation has been traditionally studied as a one-way causal relationship mediated by referral hiring. In this thesis, an alternative framework is introduced which describes the dynamic reciprocal relationships between social segregation, workplace segregation, individuals' homophily levels, and referral hiring. An agent-based simulation model was developed based on this framework. The model describes the process of continuous change in composition of workplaces and social networks of agents (individuals), and how this process affects levels of workplace segregation and the segregation of social networks of the agents. The simulation results indicated that a labour market may experience significant levels of workplace segregation and social segregation even when the hiring of workers occurs mainly through formal channels. The results also show that majority groups tend to be more homophilous than minority groups, that referral hiring may be beneficial for minority groups especially when the population is highly segregated, and that the relationship between referral hiring and minority unemployment is curvilinear. Levels of workplace and social segregation were found to be negatively correlated with minority proportion, average size of individuals' social network, and firm size, while they were positively correlated with overall unemployment level and hiring discrimination. The research is based on primary data involving structured interviews with a sample of 39 employers and 122 workers (81 Muslim and 41 Coptic workers) in industrial firms in Egypt. Two secondary data sets were also used: the Social Contract Survey (SCS) and Workers' Status in Industrial Enterprises Survey (WSIES). The data were used to assess the levels of social and workplace segregation in Egypt (which found to be high), and to validate the simulation model.

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Souza, Alessandra Magda dos Santos de. « Condomínios horizontais exclusivos e a dinâmica socioespacial no litoral metropolitano de Aracaju (SE) ». Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/5472.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
At present, exclusive horizontal condominiums (EHC's) are the subject of debate since they represent and signify the urban-regional space of contemporary cities. These type of gated condominiums are considered new forms of socio-spatial segregation. The Metropolitan Coast of Aracaju (MCA) is a complex geographic object, a hybrid character phenomenon due to the confluence between the living and the holiday, old and new, urban and rural, public and private. This thesis is based on the argument that these new urban habitats are an element that acts directly on the reconfiguration of the urban-regional space and represent one of the features of diffuse urbanization in recent decades. The following methodological procedures in the research were used: reading the literature related to the theme; collection and organization of secondary data: documentary research, mapping and statistics; EIA-RIMAs and Master Plans analysis, as well as visits to the property developers web sites in order to observe how they operate in the promotion of real estate products; observation and photographic record in loco; interviews to the shareholders; preparation of cartographic materials; analysis and interpretation of data. The qualitative approach was chosen to explain the reality based on the principle of movement and geographical totality, considering that the processes acquire meaning when they take form, the form-content. This thesis aimed to analyze the socio-spatial dynamics of MCA focusing on exclusive horizontal condominiums. He attempted to explain the origin, the meaning, the intentions and the socio-spatial consequences of this form of segregation and specific real estate product within the regional urban context. The government, the housing market and the investors represent the force that act more directly in the expansion and proliferation of homes for first or second residence in this type of habitat and nesting on the coast or in the MCA field. Two moments of EHC's phenomenon of the MCA were identified. First, in the 1990s, with the emergence and expansion of beach condos in the coastal sector of Aracaju Expansion Zone for the participation of local real estate capital. And later, in the early twenty-first century, and still in the process of expansion, the regional real estate market, national and international begins to operate in specific sectors of the metropolitan coast in beachy sector of Barra dos Coqueiros and in the countryside of São Cristóvão. These condominiums present forms and offer complex content of activities and services. The location of these developments close to major structural axes implemented by the government, as the bridge Construtor João Alves, BR 101 road, now doubled, and state highways SE 100 and SE 050, makes the phenomenon a vector in the (re)structuring of spaces scattered and disconnected from the urban center of the capital. Property developers, representatives of local capital, regional, national and international, play a crucial role in the sale and marketing of real estate product that becomes increasingly a dream of consumption and a symbol of self-realization of solvables of the population. From the view of residents, the living and spend the holidays in these closed residential spaces were clarified the changes in socio-spatial practices that have established in metropolitan coast, and further it helps to explain the self-segregation process.
Os condomínios horizontais exclusivos (CHE’s) são, na atualidade, motivo de discussão pelo que representam e significam no espaço urbano-regional das cidades contemporâneas. Recortados fisicamente no espaço, os condomínios são considerados como novas formas de segregação socioespacial. No Litoral Metropolitano de Aracaju (LMA), o caráter híbrido do fenômeno, pelo confluir do morar e do veranear, do velho e do novo, do urbano e do rural, do público e do privado, dá o tom da complexidade deste objeto geográfico. A presente tese baseia-se na discussão que esses novos habitats urbanos configuram-se como um elemento que atua diretamente na reconfiguração do espaço urbano-regional em questão e que se constitui como uma das feições da urbanização difusa que se desenha nas últimas décadas. No processo de investigação da pesquisa foram utilizados os seguintes procedimentos metodológicos: levantamento e leitura da produção bibliográfica referente ao tema proposto para pesquisa; coleta e organização dos dados secundários: pesquisa documental, cartográfica e estatística; análise de EIA – RIMAS e Planos Diretores, assim como visitas ao site de incorporadoras a fim de observar como estas atuam na promoção dos produtos imobiliários; observação e registro fotográfico in loco; realização de entrevistas aos condôminos; elaboração de material cartográfico; análise e interpretação dos dados. Partiu-se do princípio do movimento e da totalidade geográfica pela compreensão de que os processos adquirem significado quando tomam forma, a forma-conteúdo. A abordagem se fez de forma mais qualitativa com foco na explicação dos processos que caracterizam o fenômeno dos CHE’s. A presente tese teve por objetivo analisar a dinâmica socioespacial do LMA com enfoque nos condomínios horizontais exclusivos. Buscou-se explicar a gênese, o significado, as intencionalidades e os desdobramentos socioespaciais desta forma de segregação e produto imobiliário específico dentro do contexto urbano regional. O poder público, o mercado imobiliário e os condôminos representam a força que atua mais diretamente na expansão e proliferação de residências para primeira ou segunda residência dessa forma de habitat e assentamento no litoral ou no campo do LMA. Identificou-se dois momentos do fenômeno dos CHE’s no LMA. Primeiro, na década de 1990, com o surgimento e a expansão dos condomínios de praia no setor costeiro da Zona de Expansão de Aracaju pela participação do capital imobiliário local. E posteriormente, no início do século XXI, e ainda em processo de expansão, o mercado imobiliário regional, nacional e internacional passa a atuar em setores específicos do litoral metropolitano, no setor praiano da Barra dos Coqueiros e na zona rural do município de São Cristóvão com o lançamento de condomínios com formas e conteúdos mais complexos diante da gama de atividades e serviços que estes dispõem. A localização destes empreendimentos próximos a importantes eixos estruturantes implantados pelo poder público, como a ponte Construtor João Alves, a BR 101, agora duplicada, e as rodovias estaduais SE 100 e SE 050, faz do fenômeno um vetor na (re)estruturação dos espaços dispersos e desconectados do núcleo urbano da capital. Os promotores imobiliários, representantes do capital local, regional, nacional e internacional, desempenham papel crucial na venda e comercialização deste produto imobiliário que se torna cada vez mais um sonho de consumo e um símbolo da autorrealização das camadas solváveis da população. O olhar dos condôminos elucidou as mudanças nas práticas socioespaciais que o morar e o veranear nestes espaços residenciais fechados tem implantado no litoral metropolitano e ajuda a explicar a autossegregação que se processa.

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Jones, Christopher William. « Dynamics, formation and segregation of the cytoplasmic chemoreceptor cluster in Rhodobacter sphaeroides ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:73ce27e2-260e-4b1d-a746-cf7e7df6a02e.

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The internal organisation of bacteria is far more complex than originally thought. Many components of the cell have specific localisation patterns. Proteins are localised to many different regions of the cell by numerous mechanisms, and often their function depends on correct localisation. Bacterial and plasmid DNA are also highly organised and actively positioned. These tightly regulated positioning patterns ensure stable maintenance of genetic material. Members of the ParA/MinD family of ATPases are responsible for the segregation of a large number of bacterial chromosomes and plasmids. Recently members of this family have been shown to position and segregate protein complexes. One such complex is the cytoplasmic chemosensory cluster of Rhodobacter sphaeroides. This large complexes are segregated from a single cluster positioned at the mid-cell to two clusters at 1/4, 3/4 positions by the ParA homologue PpfA using the nucleoid as a scaffold. This ensures that each daughter cell inherits a cluster. This study sought to investigate this cytoplasmic chemosensory cluster, and its positioning and segregation by PpfA through the cell cycle. The use of fluorescence recovery after photobleaching revealed that like membrane bound chemoreceptor arrays the cytoplasmic cluster of R. sphaeroides is a highly stable complex. The difference seen between the cytoplasmic cluster and the data reported for the membrane bound cluster of Escherichia coli is probably due to the lack of membrane helping hold the array together. Investigation of the role of PpfA in segregation of the cytoplasmic cluster, using fluorescence imaging and single molecule tracking with a range of mutants through the cell cycle, suggest that it uses a mechanism unlike any reported for ParA homologues. Single molecule tracking of PpfA molecules shows that the chemoreceptor TlpT stabilises PpfA molecules resulting in slower diffusion of PpfA molecules at the cluster. The use of a ΔppfA mutant shows that PpfA restrains the movement of the cluster, together these results suggest a model in which TlpT stabilises PpfA’s interaction with the nucleoid and PpfA positions the cluster.

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Matos, Irina Alexandra Cardoso de. « Spatiotemporal regulation of mitotic spindle dynamics and its contribution for chromosome segregation ». Doctoral thesis, Faculdade de Medicina da Universidade do Porto, 2009. http://hdl.handle.net/10216/55513.

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Matos, Irina Alexandra Cardoso de. « Spatiotemporal regulation of mitotic spindle dynamics and its contribution for chromosome segregation ». Tese, Faculdade de Medicina da Universidade do Porto, 2009. http://hdl.handle.net/10216/55513.

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Marks, Benjamin. « Grainsize dynamics of granular flows ». Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/9372.

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This dissertation deals with the description of a granular material as a continuum with an internal coordinate that represents the grainsize distribution. The inclusion of this internal coordinate allows us to describe polydispersity in a natural and simple manner. The bulk of this dissertation is built on four published papers. Each paper is prefaced by an introductory section, where the motivation for the paper is presented. In the first paper, I show how the fundamental mechanism of granular segregation can be represented in a cellular automaton. An equivalent continuum model is derived from the rules of the cellular automaton, similar to previous theories. The second paper extends this mechanism to include arbitrary grainsize distributions in a continuum framework. This continuum description predicts not only the evolution of the grainsize distribution in space and time, but also kinematics. I show an extension of the theory in Chapter 5 so that it can be included in a numerical continuum solver. This is then used to predict steady state grainsize distributions in Chapter 6, which are shown to be a function of only the stress gradient and diffusivity. This new continuum theory predicts that segregation will create a lubrication effect that accelerates the flow. In the third paper, I show experimentally how this effect creates additional forces when a granular avalanche impacts an obstacle. At experimental scale, a 20% increase in force is measured. In the final paper, comminution is added to the grainsize framework in a new cellular automaton, allowing me to model crushable flows. I show how the grainsize distributions measured in confined comminution can be predicted from this model. Additionally, when segregation is introduced log-normal grainsize distributions develop as in avalanche flow. The transition from power law to log-normal grainsize distributions is explained as an interaction between comminution and segregation.

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Stock, Eduardo Velasco. « Ordenamento e destilação em um modelo estocástico de partículas interagentes sob contrafluxo ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/150252.

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Neste trabalho estudamos uma dinâmica estocástica de partículas de duas espécies baseada em células. Basicamente, incorporamos algumas inovações em um modelo unidimensional proposto e resolvido por R. da Silva et al. (Physica A, 2015), que considera que em um célula, na ausência de partículas da espécie contrária, a partícula vai pra frente com uma probabilidade p, que representaria um campo na direção longitudinal de um corredor e fica na própria célula com q=1-p. Contudo, essa probabilidade p é reduzida de acordo com a concentração de partículas contrárias. Nosso trabalho não apenas estendeu o problema pra duas dimensões como também incluiu aspectos relativos a colisão e o espalhamento para células vizinhas. Nossos resultados são divididos em duas situações: a) Espécie contrária permanece imóvel funcionando como obstáculos b) Espécie contrária em movimento. Na primeira situação podemos ver uma interessante transição na distribuição dos tempos de travessia em função das concentrações dos obstáculos, por monitorar a curtose da distribuição. Quando a espécie contrária se movimenta, vemos que o tempo de destilação entre as partículas (tempo para que as espécies estejam geograficamente separadas no corredor) depende do parâmetro ligado ao espalhamento transversal das partículas, parâmetro este, que não influencia no caso das partículas paradas. Finalmente nós colocamos as partículas em um sistema com condições periódicas de contorno. Neste caso, podemos observar o aparecimento de padrões de bandas longitudinais ao campo, exatamente como ocorrem em problemas de coloides carregados sob a ação de campos longitudinais e em modelos de pedestres em corredores. Mostramos como o sistema relaxa para tal tipo de estado estacionário utilizando um adequado parâmetro de ordem ligado a segregação das partículas. Nosso modelo, diferentemente dos modelos para pedestres, não se baseia em equações tipo Langevin. Nossa abordagem é totalmente estocástica e por esse ponto de vista ainda mais fundamental e geral, podendo ser estendida para mais modelos de partículas em fluxos contrários. Nossa solução vem tanto através de simulações Monte Carlo bem como soluções das equações diferenciais parciais que descrevem o sistema e que são oriundas das recorrências estabelecidas para os caminhantes aleatórios. As simulações Monte Carlo e soluções via EDP mostram boa concordância em todos os aspectos analisados, tanto qualitativa quanto quantitativamente.
In this work we study a stochastic dynamic of particles of two types based on cells. Basically we incorporate some innovations on a one-dimensional model proposed and solved by R. da Silva et al. (Physica A, 2015) which considers that in the absence of particles of the opposite species in the cell a particle goes toward the next cell with probability p and returns to the previous cell with probability q = 1 p. However this motion probability linearly decreases with the relative density of the contrary species. Our work not only expands the problem for two dimensions but also includes collision aspects by adding scattering to the neighbouring cells. Our results are divided into two di erent categories: a) One of the species remain xed in their places which means that such particles will work as obstacles; b) Both species can move in the environment. In the rst situation we can observe, by monitoring the kurtosis, that an interesting transition of the crossing time distribution arises as the concentration of the obstacles increases. When both species can move we can observe that the distillation time (spent time for the complete geographical separation of the species in the corridor) depends on the parameter related to the perpendicular scattering of the particles. This same parameter has shown no in uence over the time distributions in the rst situation. Finally we implement periodic boundary conditions in the eld's direction. In this case we are able to observe the arising of band patterns parallel to the eld's direction exactly as it does with oppositely charged colloids under the in uence of a uniform electric eld or pedestrian dynamics in corridors. We also show how the system relax to such stationary state by using a suitable order parameter related to the particles segregation. Di erently from other pedestrian dynamics models, our model is not based on a Langevin-type equation. Our approach is totally stochastic and from this point of view, more fundamental and general to be extended to more types of models considering particles under counter ow. Our solution is obtained by both Monte Carlo simulations and numerical integration of partial di erential equations (PDE) from recurrence relation of the directed random walkers. The Monte Carlo simulations and the solutions of the PDE show a good agreement in all aspects analysed both qualitatively and quantitatively.

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Hosseinpoor, Masoud. « Numerical simulation of fresh SCC flow in wall and beam elements using flow dynamics models ». Thèse, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/9808.

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Abstract : Recently, there is a great interest to study the flow characteristics of suspensions in different environmental and industrial applications, such as snow avalanches, debris flows, hydrotransport systems, and material casting processes. Regarding rheological aspects, the majority of these suspensions, such as fresh concrete, behave mostly as non-Newtonian fluids. Concrete is the most widely used construction material in the world. Due to the limitations that exist in terms of workability and formwork filling abilities of normal concrete, a new class of concrete that is able to flow under its own weight, especially through narrow gaps in the congested areas of the formwork was developed. Accordingly, self-consolidating concrete (SCC) is a novel construction material that is gaining market acceptance in various applications. Higher fluidity characteristics of SCC enable it to be used in a number of special applications, such as densely reinforced sections. However, higher flowability of SCC makes it more sensitive to segregation of coarse particles during flow (i.e., dynamic segregation) and thereafter at rest (i.e., static segregation). Dynamic segregation can increase when SCC flows over a long distance or in the presence of obstacles. Therefore, there is always a need to establish a trade-off between the flowability, passing ability, and stability properties of SCC suspensions. This should be taken into consideration to design the casting process and the mixture proportioning of SCC. This is called “workability design” of SCC. An efficient and non-expensive workability design approach consists of the prediction and optimization of the workability of the concrete mixtures for the selected construction processes, such as transportation, pumping, casting, compaction, and finishing. Indeed, the mixture proportioning of SCC should ensure the construction quality demands, such as demanded levels of flowability, passing ability, filling ability, and stability (dynamic and static). This is necessary to develop some theoretical tools to assess under what conditions the construction quality demands are satisfied. Accordingly, this thesis is dedicated to carry out analytical and numerical simulations to predict flow performance of SCC under different casting processes, such as pumping and tremie applications, or casting using buckets. The L-Box and T-Box set-ups can evaluate flow performance properties of SCC (e.g., flowability, passing ability, filling ability, shear-induced and gravitational dynamic segregation) in casting process of wall and beam elements. The specific objective of the study consists of relating numerical results of flow simulation of SCC in L-Box and T-Box test set-ups, reported in this thesis, to the flow performance properties of SCC during casting. Accordingly, the SCC is modeled as a heterogeneous material. Furthermore, an analytical model is proposed to predict flow performance of SCC in L-Box set-up using the Dam Break Theory. On the other hand, results of the numerical simulation of SCC casting in a reinforced beam are verified by experimental free surface profiles. The results of numerical simulations of SCC casting (modeled as a single homogeneous fluid), are used to determine the critical zones corresponding to the higher risks of segregation and blocking. The effects of rheological parameters, density, particle contents, distribution of reinforcing bars, and particle-bar interactions on flow performance of SCC are evaluated using CFD simulations of SCC flow in L-Box and T-box test set-ups (modeled as a heterogeneous material). Two new approaches are proposed to classify the SCC mixtures based on filling ability and performability properties, as a contribution of flowability, passing ability, and dynamic stability of SCC.
Résumé : Récemment, il y a un grand intérêt à étudier les caractéristiques d'écoulement des suspensions dans différentes applications environnementales et industrielles, telles que les avalanches des neiges, les coulées de débris, les systèmes de transport et les processus d’écoulement des matériaux. En ce qui concerne les aspects rhéologiques, la plupart des suspensions, comme le béton frais, se comportent comme un fluide non-Newtonien. Le béton est le matériau de construction le plus largement utilisé dans le monde. En raison de limites qui caractérisent le béton normal en termes de maniabilité et de capacité de remplissage de coffrage, il était nécessaire de développer une nouvelle classe de béton qui peut couler sous son propre poids, en particulier à travers les zones congestionnées du coffrage. Par conséquent, le béton autoplaçant (BAP) est un nouveau matériau de construction qui est de plus en plus utilisé dans les différentes applications. Étant donné sa fluidité élevée de BAP peut être utilisé dans certaines applications particulières, notamment dans la section densément renforcée. Cependant, la fluidité élevée rend le béton plus sensible à la ségrégation des gros granulats pendant l'écoulement (la ségrégation dynamique) et ensuite au repos (ségrégation statique). La ségrégation dynamique peut augmenter lorsque le BAP est coulé sur une longue distance ou en présence d'obstacles. Par conséquent, il est toujours nécessaire d'établir un compromis entre la fluidité, la capacité de passage, et la stabilité du BAP. Ceci doit être pris en considération afin de concevoir le processus de coulée et dosage des mélanges du BAP. Ceci est appelé la conception d'ouvrabilité du BAP. Une conception de maniabilité efficace et non coûteuse peut être achevée à travers la e prévision et l'optimisation de l'ouvrabilité des mélanges de béton pour les procédés de construction sélectionnés, notamment le transport, le pompage, la mise en place, le compactage, la finition, etc. En effet, les formulations de mélange doivent se confirmer à la qualité de la construction demandée, par exemple les niveaux exigés de fluidité, la capacité de passage, la capacité de remplissage, et la stabilité (statique et dynamique). Celui est nécessaire pour développer des outils théoriques afin d’évaluer dans quelles conditions les exigences de qualité de la construction sont satisfaites. Cette thèse est consacrée à la réaliser des simulations analytiques et numériques pour prédire la performance d'écoulement du BAP dans différents procédés de la mise en place du béton. L'objectif spécifique de cette étude consiste à simuler l'écoulement du BAP dans essais empiriques, notamment la boite en L et la boite en T pour évaluer la performance du BAP pendent la mise en place (la fluidité, la capacité de passage, la capacité de remplissage, et la ségrégation dynamique induite par cisaillement ou par gravité). Par conséquent, le BAP est modélisé comme matériau hétérogène. En outre, un modèle analytique est proposé pour prédire la performance à l'écoulement du BAP dans la boite en L en utilisant la théorie de Dam Break. D'autre part, les résultats des simulations numériques de l’écoulement du BAP dans une poutre renforcée sont comparés aux résultats expérimentaux par des profils de surface libres. Les résultats des simulations numériques de BAP coulée (modélisée comme un fluide homogène unique), sont utilisés pour déterminer les zones critiques correspondant à des risques plus élevés de ségrégation et de blocage. Les effets des paramètres rhéologiques, la masse volumique, le contenu des particules, la distribution de barres d'armature, et les interactions particule-barres sur les performances d'écoulement du BAP sont évaluées à l'aide de simulations MFN d’écoulement du BAP par les essais des L-Box et T-box (modélisée comme une matériau hétérogène). Deux nouvelles approches sont proposées pour classifier les mélanges du BAP sur la base de la capacité de remplissage, et les propriétés de performabilité, en fonction de la fluidité, la capacité de passage et de la stabilité dynamique du BAP.

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Jajoo, Rishi Har. « Experiments and Analysis of Mitochondrial DNA Segregation, Yeast Polarization and RNA Polymerase Dynamics ». Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17463961.

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This thesis presents work done in three different topics in biology with a combination of experiments, mathematical modeling and quantitative data analysis. All cellular materials are partitioned between daughters at cell division, but by different mechanisms and with different accuracy. Many macromolecules partition in proportion to cytoplasmic volume with significant errors at low numbers, while chromosomes accurately push half the copies to each cell regardless of volume. Little is known about organelles, but in Schizosaccharomyces pombe the mitochondria are pushed to the cell poles by the spindle, along with the chromosomes. Here we find that mitochondria spatially re-equilibrate just before division, and that the mitochondrial volume and DNA-containing nucleoids instead segregate in proportion to the cytoplasm inherited by each daughter. However, in contrast to other macromolecules, nucleoid partitioning errors are still strongly suppressed. This is ensured by control at two levels: mitochondrial volume is actively distributed throughout a cell in a process involving the microtubule associated protein Mmb1p, and nucleoids are spaced out in semi-regular arrays within mitochondria. The data also suggest that nucleoid replication control is passive and Poisson, and that low concentration noise is achieved by accurate segregation rather than corrective feedback control. Patterning in organisms is both beautiful and functional, but we have limited understanding of the general principles that cause patterns to emerge from isotropic initial conditions. Alan Turing proposed a minimal set of conditions that would allow reaction-diffusion systems to spontaneously form stable patterns. Since then many biological systems have been hypothesized to be of the Turing type, but with limited evidence that they actually rely on this mechanism. One of the conditions of Turing's theory is that reactions must have non-linear sensitivities (cooperativity) in their positive feedback cycles. We use a minimal model of yeast bud site selection to show that the amount of cooperativity achievable is naturally limited by the kinetic parameters achievable by proteins and the type of reaction mechanisms commonly used to achieve cooperativity. Further, higher levels of cooperativity necessarily cause pattern formation to slow down, likely causing a fitness defect for the organism. Then, because cooperativity is also used in many other biology systems, we show examples in TF-promoter binding and cooperative ligand binding where the trade-off between cooperativity speed of response is also present. These considerations bring into question how biological systems respond to these trade-offs. We then explore a conceptual model for yeast budding where an additional actin-based positive feedback loop uses a time-delay, not cooperativity, to ensure that yeast picks a single bud site. RNA polymerase II (RNAP) pauses and backtracks during transcription elongation to regulate gene expression, control transcriptional efficiency and ensure transcriptional accuracy. After a pause, RNAP often backtracks and, in the presence of TFIIS, cleaves off the 3’ end of nascent RNA, allowing productive transcription to restart. However, the precise determinants of RNAP pausing, backtracking, and restarting remain unclear. Native elongating transcript sequencing (NET-seq) visualizes RNA polymerase pausing and backtracking with nucleotide resolution. Applying NET-seq to wild-type S. cerevisiae gives locations where cleavage occurs after backtracking. In contrast, NET-seq data from a strain where TFIIS is deleted reveal the primary points of pausing. Using these data, we show that RNAP pausing is largely controlled by the relative strength of the RNA:DNA and DNA:DNA hybrids in and downstream of the transcription bubble. In addition, backtracking is likely determined by the stacking interactions between the 3’-end of nascent RNA and Tyr769 of the Rpb2 subunit of RNAP. Though other factors beyond structural energetics of the transcription elongation complex certainly play a role in RNAP backtracking, this work suggests that the ubiquity of RNAP backtracking is largely controlled by sequence elements.
Systems Biology

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Tahir, Abdifatah I. « Urban governance, land conflicts and segregation in Hargeisa, Somaliland : historical perspectives and contemporary dynamics ». Thesis, University of Sussex, 2017. http://sro.sussex.ac.uk/id/eprint/70417/.

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This thesis offers an explanation for why urban settlement in Somaliland's capital city of Hargeisa is segregated along clan lines. The topic of urban segregation has been neglected in both classic Somali studies, and recent studies of post-war state-building and governance in Somaliland. Such negligence of urban governance in debates over state-making stems from a predominant focus on national and regional levels, which overlooks the institutions governing cities. Yet urban governance can provide key insights into the nature and quality of interaction between people and the local state, and the processes of making and unmaking of Somali urban spaces. Given the rapid urban growth in the Somali populated territories, I propose a shift in focus to explore city spaces, as a means of deepening understanding of Somali social, political and spatial organisation. In advancing this proposed shift, the thesis scrutinises the nexus between governance and segregation in Hargeisa, drawing on urban ethnographic methods, interview and archival sources. I argue that segregation in the city can be understood as the spatial manifestation of governance practices across colonial and postcolonial periods, in intersection with bottom up processes, particularly the quest for security and peacebuilding in what is largely characterised as a hybrid order. The concept of hybrid governance – while capturing important aspects of control over city space - is often insufficiently historicised and politicised to convey the complex intersection of state institutions, clan and sub-clan allegiance and traditional authorities. My analysis thus situates recent urban governance and conflicts over land in a longer history of municipal governance, urban land administration and conflict adjudication. This historical perspective is important for the understanding of how segregation has been reproduced over time, and adds a new dimension to the understandings of the drivers and dynamics of Hargeisa's spatial character.

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Alsenafi, Abdulaziz. « Segregation Dynamics Motivated by Territorial Markings:The Transition from a Particle to a Continuum Model ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1467727114.

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Lim, Kok Seng. « Digital image analysis study of bubbling, solids mixing and segregation in fluidized beds / ». Title page, contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phl73212.pdf.

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Ding, Yi. « Analysis of SUMO dynamics and functions during meiosis in oocytes ». Kyoto University, 2018. http://hdl.handle.net/2433/235120.

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Carsí, Rosique Marta. « Molecular mobility. Structure-property relationship of polymeric materials ». Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/59460.

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[EN] The present work examines the influence of the chemical structure of polymers on thermal, mechanical and dielectric behavior. The experimental techniques used for the purpose are differential scanning calorimetry, dynamo-mechanical analysis and dielectric spectroscopy. Additionally, in order to confirm the results obtained using the above methods, other techniques such as ray diffraction have also been employed. Chapters 1 and 2 contain the introduction and the objectives, respectively. Chapter 3 briefly describes the experimental techniques used. Chapter 4 contains the findings of the comparative analysis of the response to electrical noise fields for three poly(benzyl methacrylates) with different structures. The analysis was carried out under a wide range of frequencies and temperatures on three poly(benzyl methacrylates) containing two dimethoxy groups in positions 2,5-, 2,3- and 3,4-. The results show that the position of the dimethoxy groups on the aromatic ring has a significant effect on the molecular dynamics of poly(benzyl methacrylate). The spectra obtained were of high complexity and therefore, in order to perform a better analysis, numerical methods for time-frequency transformation including the use of parametric regularization techniques were used. We studied the effect of this structural change on the secondary relaxation processes and relaxation process , relating to the glass transition. We also analyzed the effect of the dimethoxy group position on the formation of nanodomains, in which the side chains are predominant, and on the conduction processes of the materials tested. In Chapter 5, the conductivity of rubbery liquids was studied by analyzing poly(2,3-dimethoxybenzyl methacrylate), which exhibits its own particular behavior. The chapter analyzes the principle of time-temperature superposition, employing different interrelated variables. Chapter 6 focuses on how the presence of crosslinking affects the molecular mobility of polymethacrylates containing aliphatic alcohol ether residues. In this case, the effect of crosslinking on the secondary and primary relaxation processes was analyzed. The creation of nanodomains in the side chains as a result of the presence of crosslinking was also studied.
[ES] En este trabajo se presenta un estudio de la influencia de la estructura química de los polímeros en su comportamiento térmico, mecánico y dieléctrico. Las técnicas experimentales empleadas para ello han sido la calorimetría diferencial de barrido, el análisis dinamo-mecánico y la espectroscopia dieléctrica. Adicionalmente, se han empleado otras técnicas como la difracción de rayos, con objeto de corroborar los resultados obtenidos por las primeras. En los Capítulos 1 y 2 se recoge la introducción y los objetivos, respectivamente. El Capítulo 3 presenta una breve descripción de las técnicas experimentales empleadas. En el Capítulo 4 se recogen los resultados obtenidos en el análisis comparativo de la respuesta a campos de perturbación eléctrica en un amplio rango de frecuencias y temperaturas para tres polimetacrilatos de bencilo con dos grupos dimetoxi en posiciones 2,5-, 2,3- y 3,4-. Los resultados obtenidos señalan el importante efecto de la posición de los grupos dimetoxi en el anillo aromático, sobre la dinámica molecular del polimetacrilato de bencilo. Los espectros obtenidos fueron muy complejos, por ello en orden a llevar a cabo un mejor análisis se emplearon métodos numéricos para la transformación tiempo-frecuencia que incluyeron el uso de técnicas de regularización paramétrica. Se ha estudiado el efecto que dicho cambio estructural ejerce tanto sobre los procesos de relajación secundaria como sobre el proceso de relajación α, relacionado con la transición vítrea. Así mismo, se ha analizado el efecto de la posición de los grupos dimetoxi en la formación de iii nanodominios en los que predominan las cadenas laterales, y su efecto en los procesos de conducción de los materiales analizados. En el Capítulo 5 se recoge el estudio de la conductividad de líquidos gomosos tomando como modelo el poli (metacrilato de 2,3-dimetoxibencilo), por su peculiar comportamiento. En este capítulo se ha realizado un análisis del principio de superposición tiempo-temperatura, empleando para ello diferentes variables relacionadas entre sí. En el Capítulo 6 se recoge el efecto de la presencia de entrecruzante en la movilidad molecular de polimetacrilatos que contienen residuos de éteres de alcoholes alifáticos. En este caso, se ha analizado el efecto de la presencia de entrecruzante tanto en los procesos de relajación secundarios, como en el proceso de relajación principal. También se llevó a cabo un análisis del efecto que la presencia de entrecruzante tiene sobre la creación de nanodominios gobernados por las cadenas laterales.
[CAT] En aquest treball es presenta un estudi de la influència de l'estructura química dels polímers en el seu comportament tèrmic, mecànic i dielèctric. Les tècniques experimentals utilitzades han sigut la calorimetria diferencial de rastreig, l'anàlisi dinamo-mecànic i l'espectroscòpia dielèctrica. Addicionalment, s'han empleat altres tècniques com la difracció de rajos X a fi de corroborar els resultats obtinguts per les primeres. En els Capítols 1 i 2 s'arreplega la introducció i els objectius, respectivament. Al Capítol 3 es presenta una breu descripció de les tècniques experimentals emprades. En el Capítol 4 es recull els resultats obtinguts en l'anàlisi comparativa de la resposta a camps de pertorbació elèctrica en un ampli rang de freqüències i temperatures de tres polimetacrilats de benzil amb dos grups metoxi en posicions 2,5-, 2,3- i 3,4-. Els resultats obtinguts assenyalen l'important efecte de la posició dels grups metoxi en l'anell aromàtic, sobre la dinàmica molecular del polimetacrilat de benzil. Els espectres obtinguts van ser molt complexos, per aquesta raó per a dur a terme un millor anàlisi es van emprar mètodes numèrics per a la transformació temps-freqüència que van incloure l'ús de tècniques de regularització paramètrica. S'ha estudiat l'efecte que el dit canvi estructural exerceix tant sobre els processos de relaxació secundària com sobre el procés de relaxació , relacionat amb la transició vítria. Així mateix, s'ha analitzat l'efecte de la posició dels grups metoxi en la formació de nanodominis en els que predominen les cadenes laterals, i el seu efecte en els processos de conducció dels materials analitzats. En el Capítol 5 s'arreplega l'estudi de la conductivitat de líquids gomosos prenent com a model el poli-(metacrilat de 2,3-dimetoxibencilo), pel seu peculiar comportament. En aquest capítol s'ha realitzat un anàlisi del principi de superposició temps-temperatura, emprant per a això diferents variables relacionades entre sí. En el Capítol 6 s'arreplega l'efecte de la presència d'entrecreuat en la mobilitat molecular de polimetacrilats que contenen residus d'èters d'alcohols alifàtics. En aquest cas, s'ha analitzat l'efecte de la presència d'entrecreuat tant en els processos de relaxació secundaris, com en el procés de relaxació principal. També es va dur a terme un anàlisi de l'efecte que la presència d'entrecreuat químic té sobre la creació de nanodominis governats per les cadenes laterals.
Carsí Rosique, M. (2015). Molecular mobility. Structure-property relationship of polymeric materials [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59460
TESIS
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Buhai, Ioan Sebastian. « Essays on labour markets : worker-firm dynamics, occupational segregation and workplace conditions = Essays over Arbeidsmarkten / ». [Amsterdam] : Rotterdam : Thela Thesis ; Erasmus University [Host], 2008. http://hdl.handle.net/1765/13965.

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Rajasingam, Saima. « The dynamics of auditory stream segregation for tone sequences with gradually and abruptly varying stimulus properties ». Thesis, Aston University, 2017. http://publications.aston.ac.uk/30818/.

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The nine experiments presented within this thesis explored the dynamics of stream segregation in repeating ABA tone sequences with gradual or abrupt changes in their acoustic properties. Experiments 1-6 used a continuous monitoring method to investigate the effect of these changes on the number of streams perceived (1 or 2). Experiments 1 and 2 demonstrated that abrupt and gradual changes in sequence base frequency had a much stronger effect on the build-up of streaming over time than those in interaural time difference (ITD), an outcome consistent with either functional or neural accounts of the build-up of segregation. Experiments 3 and 4 demonstrated that abrupt changes either in timbre (using pure tones and narrowly spaced tone dyads) or level could produce resetting (partial loss of build-up) but that the direction of the transition was important. Notably, an overshoot in stream segregation followed the tone-to-dyad transition, despite no significant change in the pattern of peripheral excitation. Experiments 6 and 7 demonstrated that resetting was not a result of correlated changes in A and B tone subsets. In both experiments, anti-correlated level changes tended to produce resetting (B"A#) and overshoot (B#A"), respectively. This outcome favours a neural mechanism of build-up based on subtractive adaptation. Experiments 7-9 investigated the influence of an induction sequence on the perception of a subsequent test sequence. Experiments 7 and 8 achieved capture of a tone subset in the test sequence by adjusting the difference in frequency or level between inducer tone subsets, such that only one subset matched its test-sequence counterpart. This resulted in greater stream segregation. Experiment 9 attempted capture using a harmonic complex synchronous with the lower subset. However, the fusion of the synchronous complex with the corresponding tone subset failed to disrupt capture, presumably because it did not change the rhythm of the sequence. Overall, these experiments demonstrate that abrupt changes in stimulus properties can cause resetting of build-up or overshoot, depending on the nature of the transitions, and stream capture can be achieved by manipulating the difference between tone subsets in an inducer.

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Chun, Byeongjae. « Characterization of nano-phase segregation in multicompartment micelle and its applications : Computational approaches ». Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54416.

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Computational methodologies were employed to study a supramolecular micellar structure and its application, nanoreactor. This task was done through rigorous scale-up procedure using both atomistic and mesoscopic simulations. Primarily, density functional theory (DFT) calculation was used to characterize the smallest unit of complex molecules in the multicomponent mixture system. The following step involved transferring the information achieved by DFT calculation to larger scale simulation, such as molecular dynamics (MD) simulation. Lastly, based on the atomistic simulation results, we performed a series of dissipative particle dynamics (DPD) simulations to study a full body of polymeric multicompartment micelle. In the course of research, we built a systematic procedure to minimize the complexity of computation and efficiently characterize macromolecular structures and its application.

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Sousa, Da Costa Maria Judite. « Csi2 modulates microtubule dynamics and helps organize the bipolar spindle for proper chromosome segregation in fission yeast ». Paris 6, 2013. http://www.theses.fr/2013PA066626.

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Proper chromosome segregation is of paramount importance for proper genetic inheritance. Defects in chromosome segregation can lead to aneuploidy, which is a hallmark of cancer cells. Eukaryotic chromosome segregation is accomplished by the bipolar spindle. Additional mechanisms such as the spindle assembly checkpoint and centromere positioning further help to ensure complete segregation fidelity. We present here the fission yeast csi2+. Csi2p localizes to the spindle poles, where it regulates mitotic microtubule dynamics, bipolar spindle formation, and subsequent chromosome segregation. The bipolar mitotic spindle contains many short dynamic microtubules of ~1 micron scale, this represents a challenge for live cell imaging because the typical maximum resolution of the optical microscope is ~λ/2 or ~300 nm. We developed a novel method to image short fission yeast mitotic microtubules using the thermosensitive reversible kinesin-5 cut7. 24ts to create monopolar spindles. Csi2-deletion (csi2Δ) results in abnormally long mitotic microtubules, high rate of transient monopolar spindles, and a subsequent high rate of chromosome segregation defects. As csi2Δ has multiple phenotypes, it enables estimates of the relative contribution of the different mechanisms to the overall chromosome segregation process. Centromere positioning, microtubule dynamics, and bipolar spindle formation can all contribute to chromosome segregation. Our data suggests that the major determinant of chromosome segregation defects may be microtubule dynamic defects
La ségrégation correcte des chromosomes est processus fondamental pour maintenir la stabilité génomique. Des défauts de ségrégation sont souvent à l’origine de l’apparition de cellules aneuploïdes, caractéristique fréquemment observée dans les cellules cancéreuses. Dans les cellules eucaryotes, la ségrégation correcte des chromosomes est assurée par le fuseau mitotique. Des mécanismes de contrôle, tels que le point de contrôle mitotique et le bon attachement des centromères, sont mis en œuvre pour assurer la bonne ségrégation des chromosomes. Dans cette étude, nous avons pu établir chez le levure fissipare, que la protéine csi2, localisée aux pôles du fuseau mitotique, joue un rôle sur la dynamique des MTs mitotiques, dans la formation d’un fuseau mitotique intègre et par conséquent dans la ségrégation correcte des chromosomes. Les MTs composants le fuseau mitotique bipolaire sont dynamiques et de petite taille ~1µm ce qui représente un défis technique pour les imager, en effet, la résolution optique d’un microscope ~λ/2 est en général de 300nm. Nous avons développé une nouvelle approche pour imager les MTs mitotiques basée sur l’utilisation du mutant réversible thermosensible kinesin-5 cut7. 24ts, pour obtenir des cellules ayant des fuseaux monopolaires. Ainsi, nous avons pu mettre en évidence que la délétion de la protéine csi2 chez la levure S. Pombe était à l’origine d’un allongement de la longueur des microtubules mitotiques, d’une augmentation du nombre de cellules présentant un fuseau monopolaire et d’une augmentation des défauts de ségrégation des chromosomes. L’étude de l’implication de la protéine csi2 dans ces différents mécanismes nous a permis de mettre en évidence la contribution de chacun de ces mécanismes dans la bonne ségrégation des chromosomes. Nous proposons dans cette étude que le facteur déterminant à l’origine d’une ségrégation incorrecte des chromosomes serait majoritairement imputable à des défauts de régulation de la dynamique des microtubules

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James, Rosalina Dee. « Cohesin proteins SMC1 and SMC3 : roles in aneuploidy and in meiotic chromosome dynamics / ». Thesis, Connect to this title online ; UW restricted, 2002. http://hdl.handle.net/1773/6333.

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Graf, Brolund Alice. « Compartmental Models in Social Dynamics ». Thesis, Uppsala universitet, Avdelningen för systemteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448163.

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The dynamics of many aspects of social behaviour, such as spread of fads and fashion, collective action, group decision-making, homophily and disagreement, have been captured by mathematical models. The power of these models is that they can provide novel insight into the emergent dynamics of groups, e.g. 'epidemics' of memes, tipping points for collective action, wisdom of crowds and leadership by small numbers of individuals, segregation and polarisation. A current weakness in the scientific models is their sheer number. 'New' models are continually 'discovered' by physicists, engineers and mathematicians. The models are analysed mathematically, but very seldom provide predictions that can be tested empirically. In this work, we provide a framework of simple models, based on Lotka's original idea of using chemical reactions to describe social interactions. We show how to formulate models for social epidemics, social recovery, cycles, collective action, group decision-making, segregation and polarisation, which we argue encompass the majority of social dynamics models. We present an open-access tool, written in Python, for specifying social interactions, studying them in terms of mass action, and creating spatial simulations of model dynamics. We argue that the models in this article provide a baseline of empirically testable predictions arising from social dynamics, and that before creating new and more complicated versions of the same idea, researchers should explain how their model differs substantially from our baseline models.
Matematiska modeller kan hjälpa oss att förstå många typer av sociala fenomen, som ryktesspridning, spridning av memes, gruppbeslut, segregation och radikalisering. Det finns idag otaliga modeller för sociala beteenden hos människor och djur, och fler presenteras kontinuerligt. Det stora antalet modeller försvårar navigering inom forskningsfältet, och många av modellerna är dessutom komplicerade och svåra att verifiera genom experiment. I detta arbete föreslås ett ramverk av grundläggande modeller, som var och en modellerar en aspekt av socialt beteende; det gäller sociala epidemier, cykler, gemensamt handlande, gruppbeslut, segregation och polarisering. Vi menar att dessa modeller utgör majoriteten av de verifierbara aspekter av socialt beteende som studeras, och att de bör behandlas som en utgångspunkt när en ny modell ska introduceras. Vilka av mekanismerna från utgångspunkten finns representerade i modellen? Skiljer den sig ens nämnvärt från utgångspunkten? Genom att ha en god förståelse för grundmodellerna, och genom att förklara på vilket sätt en ny modell skiljer sig från dem, kan forskare undvika att presentera modeller som i praktiken är mer komplicerade varianter av sådana som redan finns. I detta arbete visar vi hur dessa grundläggande modeller kan formuleras och studeras. Modellerna bygger på enkla regler om vad som händer när individer i en befolkning möter varandra. Till exempel, om en person som har vetskap om ett rykte träffar någon som inte har det, kan ryktet spridas vidare. Därför har antaganden om vilka personer som kan träffa varandra stor påverkan på de resultat som modellerna ger. I detta arbete studeras varje modell med två olika metoder: i den ena har alla personer i befolkningen samma sannolikhet att träffa varandra, i den andra representeras befolkningen av ett rutnät, där varje plats motsvarar en individ. I den senare har alltså varje person ett begränsat antal grannar att interagera med. Vilken av dessa två metoder man väljer har stor betydelse för vilka beteenden modellerna förutspår. Som ett komplement till detta arbete presenteras ett verktyg i form av ett Python-program som utför analysen av modellerna. Detta kan användas för att undersöka grundmodellerna som presenteras i detta arbete, men också för att formulera och analysera nya modeller på samma sätt. På det viset kan nya modeller enkelt jämföras mot grundmodellerna. Verktyget är användbart både som introduktion för de som är nya inom social dynamik, men också för de forskare som som vill ta fram nya modeller och föra forskningsfältet vidare.

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Liu, Boxi. « Synthesis and Surface Dynamics of Comb Polystyrenes and Their Interfacial Segregation and Bulk Thermodynamics in Blends with Linear Polystyrenes ». University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1356108332.

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Rajasimha, Harsha Karur. « Insights Into Mitochondrial Genetic and Morphologic Dynamics Gained by Stochastic Simulation ». Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/29961.

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MtDNA mutations in mammalian cells are implicated in cellular ageing and encephalomyopathies, although mechanisms involved are not completely understood. The mitochondrial genetic bottleneck has puzzled biologists for a long time. Approximate models of genetic bottleneck proposed in the literature do not accurately model underlying biology. Recent studies indicate mitochondrial morphology changes during cellular aging in culture. In particular, the rates of mitochondrial fission and fusion are shown to be in tight balance, though this rate decreases with age. Some proteins involved in mitochondrial morphology maintenance are implicated in apoptosis. Hence, mitochondrial genetic and morphologic dynamics are critical to the life and death of cells. By working closely with experimental collaborators and by utilizing data derived from literature, we have developed stochastic simulation models of mitochondrial genetic and morphologic dynamics. Hypotheses from the mitochondrial genetic dynamics model include: (1) the decay of mtDNA heteroplasmy in blood is exponential and not linear as reported in literature. (2) Blood heteroplasmy measurements are a good proxy for the blood stem cell heteroplasmy. (3) By analyzing our simulation results in tandem with published longitudinal clinical data, we propose for the first time, a way to correct for the patient's age in the analysis of heteroplasmy data. (4) We develop a direct model of the genetic bottleneck process during mouse embryogenesis. (5) Partitioning of mtDNA into daughter cells during blastocyst formation and relaxed replication of mtDNA during the exponential growth phase of primordial germ cells leads to the variation in heteroplasmy inherited by offspring from the same mother. (6) We develop a “simulation control” for experimental studies on mtDNA heteroplasmy variation in cell cultures. Hypothesis from the mitochondrial morphologic dynamics model: (7) A cell adjusts the mitochondrial fusion rate to compensate for the fluctuations in the fission rate, but not vice versa. A deterministic model for this control is proposed. Contributions: extensible simulation models of mitochondrial genetic and morphologic dynamics to aide in the powerful analysis of published and new experimental data. Our results have direct relevance to cell biology and clinical diagnosis. The work also illustrates scientific success by tight integration of theory with practice.
Ph. D.

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Mhanna, Ramona. « Confinement-induced nano-segregationof binary liquids with amphiphilic interactions ». Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S107/document.

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Le travail de cette thèse vise à contrôler la formation d’une structure fortement ordonnée à l’échelle supramoléculaire d'un liquide associé, par dilution dans un liquide aprotique, ou par confinement dans un silicate mésoporeux (MCM-41, SBA-15). Dans le volume, une forte perturbation du mélange idéal représentée en termes de regroupement entre les espèces similaires est observée par la diffusion de neutrons aux petits angles. Sous confinement, un phénomène remarquable de nanoségrégation des mélanges dans les pores conduit à des structures concentriques tubulaires de type coeur-gaine, ce qui est surprenant pour les systèmes binaires macroscopiquement homogène et entièrement miscibles. La dynamique moléculaire de ces nanostructures originales est étudiée par diffusion quasiélastique de neutrons dans le liquide et les états vitreux, révélant différents types de modes de relaxation sous confinement et étant fortement dépendant de la concentration. L’étiquetage isotopique HD des composants des mélanges fournit un point de vue global unique sur les propriétés de ces liquides binaires confinés. Ceci permet d’établir une corrélation directe entre les hétérogénéités dynamiques spatialement distinctes et la formation de nanostructures d'enveloppe de base d'origine induites par des interactions préférentielles
The objective of this thesis is tuning the formation of ordered supramolecular structures of an H-bonded liquid alcohol, either by dispersion in an aprotic solvent or by confinement in mesoporous silicates (MCM-41 and SBA-15). In the bulk, a strong perturbation from ideal mixing depicted in terms of clustering between similar species is observed by small angle neutron scattering. Under confinement, a remarkable nanosegregation phenomenon of the mixture is observed in the pores, leading to concentric tubular structures of core-shell type, which are striking for macroscopically homogeneous and fully miscible binary systems. The molecular dynamics of these original glassforming nanostructures is studied by quasielastic neutron scattering in the liquid and vitreous states, revealing different types of relaxation modes under confinement with nontrivial concentration dependencies. Isotopic HD labelling of the mixtures components provides a unique comprehensive viewpoint on the properties of these confined binary liquids, establishing a direct correlation between spatially segregated dynamical heterogeneities and the formation of original core shell nanostructures induced by preferential interactions

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Ganesan, Hariprasath [Verfasser], Alexander [Gutachter] Hartmaier et Godehard [Gutachter] Sutmann. « Highly parallel molecular dynamics / Monte Carlo coupling towards solutes segregation modelling / Hariprasath Ganesan ; Gutachter : Alexander Hartmaier, Godehard Sutmann ; Fakultät für Maschinenbau ». Bochum : Ruhr-Universität Bochum, 2019. http://nbn-resolving.de/urn:nbn:de:hbz:294-64706.

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Wang, Shih-fan. « Synthesis and Characterization of Surface Relaxations of Macrocyclic Polystyrenes and Interfacial Segregation in Blends with Linear Polystyrenes ». University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1322506008.

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Eckert, Carrie Ann. « Implications and dynamics of pericentric cohesin association during mitosis in Saccharomyces cerevisiae / ». Connect to full text via ProQuest. IP filtered, 2006.

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Thesis (Ph.D. in Molecular Biology) -- University of Colorado, 2006.
Typescript. Includes bibliographical references (leaves 126-147). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;

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Guo, Hao. « Role of Chemical Surface Preference in Translational and Reorientational Nanoconfinement ». University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1533060989864433.

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Dreißig, Steven [Verfasser]. « Development of single-cell analysis methodologies to investigate segregation and dynamics of defined genomic regions during meiosis and interphase : [kumulative Dissertation] / Steven Dreißig ». Halle, 2018. http://d-nb.info/1160514542/34.

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Almeida, Diego Ferreira de. « Competição entre dinâmica individual e coletiva em modelos de agentes econômicos ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06112015-143823/.

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Usando a generalização de Grauwin et al. [Ref. 3] do modelo de segregação de Schelling foi possível estudar, em um modelo simplificado, as consequências da guerra fiscal travada entre os estados de uma federação e os resultados da chamada guerra da taxa que os bancos adotaram depois de implantada a portabilidade de crédito bancário. No modelo de Grauwin a cidade é dividida em Q quarteirões e todos os quarteirões possuem a mesma função utilidade dependente da densidade u(m,?), que mede a satisfação dos agentes que ali residem. Inserimos um parâmetro de desordem m_b em um dos blocos para torná-lo mais atrativo que os demais. Ter um dos blocos diferente é a essência do modelo de guerra entre os quarteirões. Foi analisada uma aplicação deste modelo fazendo um paralelo com o cenário de uma guerra fiscal entre os estados de uma nação. Para tal, interpretamos os agentes econômicos como sendo as de indústrias (ou pessoas) que tomam decisões em busca de aumentar sua própria satisfação e os quarteirões como os estados de uma federação. A guerra fiscal é um instrumento usado por alguns estados brasileiros que reduzem impostos, cedem terrenos, fornecem infra-estrutura, etc para atrair investimentos na sua região. Esta guerra no primeiro momento pode ser benéfica para a sociedade, pois contribui para a descentralização da economia e reduz as diferenças de PIB e social entre os estados. Porém, em âmbito nacional, o embate econômico entre os estados geralmente resulta em perda de arrecadação para a nação. Um Estado totalmente desocupado, caso queira roubar empresas de Estados já consolidados, precisa dar muito mais incentivos para atrair investimento por conta da sua baixa população e consequentemente baixa utilidade. Neste trabalho tentamos quantificar os gastos que os Estados têm com este tipo de ação. Outra releitura dos resultados pode ser aplicada ao modelo de portabilidade de crédito, onde interpretamos os agentes econômicos de Grauwin como tomadores de empréstimo e os quarteirões como bancos de crédito ao varejo. A taxa de juros cobrada de cada banco dependerá do tamanho da carteira que este possui. Ter um banco com uma taxa de juros diferenciada o torna mais atrativo que os demais e este começa a roubar clientes dos outros bancos, contudo, o mercado reage e também reduz suas taxas, criando uma guerra da taxa no mercado financeiro. Estudando o cenário egoísta (onde o governo não desestimule a troca entre bancos) e supondo que a quantidade de tomadores no mercado seja suficientemente pequena, a dinâmica conduzirá a uma situação onde teremos apenas alguns bancos coexistindo e outros falindo. No limite egoísta o banco que se dispôs a dar incentivo terá a carteira maior que os demais bancos com taxas menores e isto vai ser invertendo à medida que o governo impõe comportamento mais altruísta da sociedade. Estudamos analiticamente os efeitos das variações da densidade e dos parâmetros (m) e altruísmo (a) no cenário global bem como os resultados esperados com a inserção de uma desordem (m_b) em um dos blocos. E por fim foram feitas simulações em computador para verificar se comportamento das dinâmicas em todos os cenários eram compatíveis com as soluções obtidas.
Using Grauwins generalization [Ref. 3] of Schelling\'s segregation model we study, in a simplified model, some consequences of the \"fiscal war\" waged between the states of a federation, and of the rate tax generated by the recent Brazilian Central Bank regulation of bank credit portability. In Grauwins model the city is divided into blocks and all blocks have the same utility function, which measures the satisfaction of agents living there and depends on the density of agents. We introduced a disorder parameter in one of the blocks to make it more attractive than the others, in order to mimick the essential igredient of competition between states or banks. We first analyze an application of this model in the scenario of a fiscal war between the states of a nation. We interpret blocks as the states of a federation and economic agents as the industries (or people) who make decisions seeking to increase their own satisfaction. The fiscal war is an instrument used by some Brazilian states consisting in reducing taxes, subsidize land, provide infrastructure, etc in order to attract investment. This war at first can be beneficial for society as it contributes to the decentralization of the economy and reduces the differences of GDP and social discrepancies between states. Nationwide, however, the economic struggle between states usually results in loss of revenue at the global level. A vacated state, in order to attract agents already established elsewhere, need to give more incentives to attract investment because of its low population and consequently low utility. In this work we try to quantify the costs that states have with this kind of action. Another analysis of the results can be applied to a bank credit portability model, where we interpret economic agents as customers and blocks as retail credit banks. The interest rate levied on each bank will depend on the size of the portfolio of that bank. Having a bank with a differentiated interest rate makes it more attractive than others, and it begins to \"steal\" customers from other banks.However, those react and also reduce their rates, creating a \"war tax\" in the financial market. Studying the selfish scenario (where the government doesnt discourage a client from taking his/her debt to another bank), and assuming that the number of customers in the market is sufficiently small, the dynamics leads to a situation where we have just a few coexisting banks, the others having gone bankrupt. In the selfish limit the bank that was willing to give encouragement will have the largest portfolio while offering lower interest rates than the others, but this will be reversed as the government imposes a more altruistic behavior to the clients. We study analytically the effects, at the global level, of variations in the density, in the altruism parameter and in the parameter determining the utility function at saturation, as well as the effects of introducing disorder in one or more blocks. Finally, computer simulations were performed to check that the dynamic behavior in all scenarios was consistent with those obtained solutions.

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Мних, Антон Сергійович, Антон Сергеевич Мных et Anton Mnyh. « Повышение энергоэффективности тепловых процессов окускования сыпучих материалов при интенсификации сегрегации в стационарных слоях ». Дисертація, ЗДІА, 2016. https://dspace.znu.edu.ua/jspui/handle/12345/823.

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RU : Диссертация посвящена комплексному решению проблемы повышения энергоэффективности окускования сыпучих материалов со снижением расхода твердого топлива за счет управления сегрегационными процессами, что позволяет стабилизировать тепловой режим обработки материала по горизонтам слоя. Теоретическими расчетами, результатами математического моделирования, посредством полупромышленного эксперимента подтверждена возможность снижения расхода твердого топлива и повышения выхода годного при агломерации железорудных, бокситовых материалов и обжиге железорудных окатышей за счет формирования слоя подготовленного к тепловой обработке с заданными химико-гранулометрическими характеристиками. Развиты научные основы повышения энергоэффективности процесса дробления и предложена методика расчета производительности четырехвалковой дробилки. Проведены исследования по рационализации режимов работы агрегата при измельчении коксовой мелочи и антрацитового штыба. Предложена новая схема дробления топлива с целью снижения влияния истирающих нагрузок на измельчаемый материал. Установлено влияние крупности дробленого топлива на время его выгорания. Реализовано математическое описание тепловых процессов в стационарном слое моно- и полидисперсных материалов с учетом внутренних источников энергии. Разработана численная конечно-элементная модель теплового режима процесса окускования. Сделан вывод, что при агломерации железорудной шихты существует рациональная температура зоны горения составляющая 1280…1340° С, и 1290…1380° С при агломерации бокситов, при которой образуется мелкопористый, легковосстановимый агломерат с достаточной прочностью. Получили дальнейшее развитие исследования направленные на стабилизацию температурно-временного режима обжига окатышей, установлено количество тепловой энергии, необходимой для обжига окатышей различного диаметра, и требуемое время обработки. Установлена необходимость разделения классов крупности окатышей и их дифференцированной укладки по горизонтам слоя. Предложена конструкция загрузочного устройства окатышей. Разработана методика, позволяющая в непрерывном режиме реального времени оценивать распределение фракционного состава шихты по горизонтам слоя подготовленной к спеканию. Проверено адекватность предложенной методики для условий аглофабрик различных предприятий. Исследована динамика процесса формирования слоя сыпучего материала. Разработана методология расчета конструктивных характеристик загрузочных узлов. Синтезирован алгоритм и программное обеспечение для оптимизации структуры слоя агломерационной шихты. Предложенные решения для условий агломерации железорудной шихты позволили сократить удельное потребление твердого топлива с 3,6…3,8 % до 3,3 % (9,81…15,14% отн.). Стабилизация теплового режима процесса спекания, позволила повысить механическую прочность и выход годного на 4,22 %. Усиление сегрегационных процессов в слое с общим сокращением содержания топлива в шихте, снижает выбросы CO на 6,55% (отн.), CO2 на 6,54% (отн.) и SO2 на 7,18% (отн).
UA : Дисертація присвячена комплексному вирішенню проблеми підвищення енергоефективності згрудкування сипучих матеріалів зі зменшенням витрати твердого палива за рахунок керування сегрегаційними процесами, що дозволяє стабілізувати тепловий режим обробки матеріалу по горизонтах шару при агломерації залізорудних, бокситових матеріалів та випалу залізорудних котунів. Отримали подальшого розвитку наукові основи підвищення енергоефективності процесу подрібнення палива. Запропоновано нову схему подрібнення з метою зменшення впливу стираючих навантажень на матеріал, що подрібнюється. Реалізовано математичний опис теплових процесів у стаціонарному шарі моно- та полідисперсних матеріалів з урахуванням внутрішніх джерел енергії. Встановлено раціональну температуру зони горіння у шарі залізорудного матеріалу, яка складає 1280...1340° С й 1290…1380° С для умов агломерації бокситів, при якій утворюється дрібнопористий, легковідновлюваний агломерат з достатньою міцністю. Отримали подальшого розвитку дослідження спрямовані на стабілізацію температурно-часового режиму випалу котунів. Встановлено необхідність розділу класів крупності котунів й їх диференційованого укладання по горизонтах шару. Запропоновано конструкцію завантажувального пристрою котунів. Синтезовано алгоритм й програмне забезпечення для оптимізації структури шару агломераційної шихти. Запропоновані рішення для умов агломерації залізорудної шихти дозволили зменшити питоме споживання твердого палива з 3,6…3,8 % до 3,3 % (9,81…15,14% відн.), підвищити вихід придатного на 4,22 %, зменшити викиди CO на 6,55% (відн.), CO2 на 6,54% (відн.) й SO2 на 7,18% (відн).
EN : The dissertation focuses on the complex solution of the problem of energy efficiency of bulk materials agglomerating with consumption of solid fuel decrease by segregation processes controlling which allows to stabilize the thermal regime of granular material sintering by horizons of the layer during sintering of iron ore, bauxite materials, and firing of iron ore pellets. The scientific bases of increase of efficiency of fuel crushing process are further developed. In order to reduce the effect of erasing loads on the material, a new scheme of fuel crushing is reveal. The mathematical description of thermal processes in a stationary layer of mono - and polydisperse materials considering the internal sources of energy is implemented. The rational temperature of the combustion zone in a layer of iron ore sinter in the range 1280...1340° С and 1290…1380° С in case of sintering bauxite which improves the quality of sinter is reveal. The conducted research is aimed at stabilizing the temperature-time regime of pellet firing. The necessity of separation of size fractions of pellets and their differentiated download by the horizons of the layer is defined. The design of the loading device of the pellets is proposed. The algorithm and software for the optimization of the sinter mix structure layer is synthesized. As the result of the research, a new methodology of forming a layer structure allows to reduce the specific consumption of solid fuel from 3,6…3,8 % to 3,3 % (9,81…15,14% cond.) increase productivity by 4,22 %, reduce harmful emissions by CO at 6,55% (cond.), by CO2 at 6,54% (cond.) and SO2 at 7,18% (cond.).

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Pallarés, Picazo Vicente. « Individual traits versus invariances of cognitive functions : a model-based study of brain connectivity ». Doctoral thesis, Universitat Pompeu Fabra, 2019. http://hdl.handle.net/10803/666806.

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Es conocido en la literatura de neuroimagen que las redes cerebrales funcionales reflejan rasgos personales. Estas características individuales, podrían interferir al caracterizar la cognición entendida como la manera en que se coordinan las redes para realizar una tarea, como mantener la atención, recordar, o procesar información visual. Cómo estos aspectos individuales coexisten con mecanismos generales es, por tanto, una pregunta clave en investigación sobre conectividad cerebral. Este trabajo estudia la relación entre marcadores de conectividad específicos tanto de sujetos, como de tareas. Se centra en dos escalas temporales distintas: la variabilidad entre sesiones, y las fluctuaciones rápidas producidas durante una sesión de adquisición. Utilizamos técnicas de machine learning para separar cuantitativamente las contribuciones de información del sujeto y del estado cognitivo a la conectividad. La metodología presentada nos permite extraer aquellas redes representativas de ambas dimensiones, así como profundizar en su evolución, sugiriendo las escalas temporales relevantes en la cognición.
És conegut en la literatura de neuroimatge que les xarxes cerebrals funcionals reflecteixen trets personals. Aquestes característiques individuals podrien interferir en caracteritzar la cognició entesa com la manera en què les xarxes es coordinen per realitzar una tasca, com mantenir l'atenció, recordar o processar informació visual. Cóm aquests aspectes individuals coexisteixen amb mecanismes generals, és, per tant, una pregunta clau en recerca sobre connectivitat cerebral. Aquest treball estudia la relació entre marcadors de connectivitat específics tant de subjectes, com de tasques. Se centra en dues escales temporals: la variabilitat entre sessions, i les fluctuacions ràpides produïdes durant una sessió d'adquisició. Utilitzem tècniques de machine learning per separar quantitativament les contribucions d'informació del subjecte i de l'estat cognitiu a la connectivitat. La metodologia presentada ens permet extreure aquelles xarxes representatives d'ambdues dimensions, així com aprofundir en la seva evolució, suggerint les escales temporals rellevants en la cognició.
There is consistent evidence in the neuroimaging literature that functional brain networks reflect personal traits. Individual specificity may interfere with the characterization of cognition, in terms of coordination of brain networks to perform a task, such as sustained attention, memory retrieval or visual information processing. How individual traits coexist with invariant mechanisms is, therefore, a key question in brain connectivity research. This work aims to examine the relationship between subject- and task-specific connectivity signatures. It focuses on two different timescales: day-to-day variability and faster fluctuations exhibited within a scanning session. We adopt a machine learning approach to quantitatively disentangle the contribution of subject information and cognitive state to the connectivity patterns. The proposed methodology allows us to extract the specific brain networks that support each of the two dimensions, as well as to delve into their changes over time, suggesting the relevant timescales for cognition.

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Guillard, François. « Trainée et portance dans les milieux granulaires ». Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4782/document.

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Cette thèse présente une étude expérimentale et numérique des forces s'exerçant sur un objet en mouvement dans un milieu granulaire. La compréhension précise de ces forces présente en effet d'importants intérêts fondamentaux (rhéologie des milieux granulaires, phénomène de ségrégation) et appliqués (robotique, locomotion animale ...). Expérimentalement, un cylindre horizontal est mis en rotation à faible vitesse dans un bac de billes de verre. Les forces s'exerçant sur cet objet dans la direction du mouvement (forces de traînée) et dans la direction verticale (forces de portance) sont mesurées.Lors du premier demi-tour, avant que le cylindre ne repasse dans son propre sillage, nous mettons en évidence l'existence d'une force de portance élevée sur l'objet (bien qu'il soit symétrique), de l'ordre de 20 fois la poussée d'Archimède du milieu, et indépendante de la profondeur. Des études numériques de dynamique moléculaire (méthode éléments discrets) permettent de comprendre comment cette portance émerge de la modification de l'écoulement granulaire par la présence d'un gradient de pression dans le milieu. Aux temps longs, après plusieurs rotations du cylindre, on observe une chute de la force de traînée, qui devient indépendante de la profondeur. Le milieu se structure sous l'effet des passages répétés du cylindre dans son sillage, ce qui écrante le poids des grains situés au dessus. Enfin, une étude numérique des forces sur une grosse particule en écoulement avec le milieu granulaire est ébauchée, en lien avec le phénomène de ségrégation granulaire
This thesis presents an experimental and numerical study of the forces experienced by an object moving in granular media. This problem, which is of practical importance in many applications (robots, animal locomotion), is also of fundamental interest (rheology of granular materials, granular segregation). The experiment consists in a horizontal cylinder rotating around the vertical axis in glass beads. Both drag forces and lift forces experienced by the cylinder are measured.During the first half rotation, before the cylinder crosses its own wake, we measure a strong lift force (despite the symmetry of the object), about 20 times the buoyancy of the cylinder, and independent of its depth. Molecular dynamic simulations (Discrete Element Method) shed lights on how this lift force arises from the modification of the grain flow due to the pressure gradient in the medium. After several rotations, when the cylinder goes through its own wake, the drag force drops and becomes independent of depth. The rotation of the cylinder induces a structure in the granular packing, which screens the weight of the grains above it. Finally, a numerical study of forces on a large particle flowing with the granular medium is sketched, in relation with the phenomenon of granular segregation

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Teixeira, Raoni Marques. « A ação do setor imobiliário na produção do espaço urbano de Novo Hamburgo / RS (1983-2012) ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/134410.

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Esta dissertação possui como tema a ação do setor imobiliário na produção do espaço urbano de cidades em processo de reestruturação econômica. O objeto de estudo é a produção de edifícios residenciais em Novo Hamburgo/RS entre 1983 e 2012, período em que houve uma grande transformação de sua base produtiva, tradicionalmente vinculada ao setor coureiro-calçadista. Busca-se, como objetivo geral da pesquisa, analisar a dinâmica imobiliária da cidade a partir da atuação dos incorporadores imobiliários, no contexto da desindustrialização em curso na região. A proposição apresentada é que a reestruturação em curso vem reforçando a segregação socioespacial característica da estrutura urbana da cidade, cujo processo de urbanização se deu de modo socialmente estratificado no espaço. Busca-se ainda, utilizando como referencial teórico a produção do espaço urbano no capitalismo, apresentar uma caracterização socioeconômica de Novo Hamburgo em contexto histórico e regional e mapear a distribuição dos investimentos imobiliários na cidade, verificando os processos socioespaciais vinculados à dinâmica imobiliária das últimas décadas.
This master´s thesis has as theme the action of real estate capital in the production of urban space in cities in the restructuring process. The study object is the production of residential buildings in Novo Hamburgo/Brazil in the period of 1983-2012. At this time, happened a biggest transformation of the productive base, which is historically related to the leather-footwear industry. The general objective of the research was analyze the city's real estate dynamics from the builders activities in the context of industrialization underway in the region. The supposition presented is that the current urban restructuring has reinforced the social-spatial segregation feature of the city, whose urbanization historically occurred inequality in space, according to its social stratification. The intention is to use the theory of production of urban space in capitalism to present a socioeconomic characterization of Novo Hamburgo in historical and regional context, and map the distribution of real estate investments in the city, checking the socio-spatial processes linked to the dynamics real estate in decades.

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