Dissertations / Theses on the topic 'Primitive states'

This thesis examines the question of how primitive states form. The first part of the thesis defines a state. I then analyse Hobbes�s Theory of the Commonwealth by Acquisition (TCA), expounded in Leviathan. I conclude that this theory fails as an answer to the question of how primitive states form as it suffers from at least five major flaws. I go on to explain, modify and correct Hobbes�s TCA through techniques that have been used in modern critiques of Hobbes�s Theory of the Commonwealth by Institution. The result is the strongest possible answer that Hobbes can give to the question of how primitive states form. I conclude that his attempt fails as even if the technical aspects of his theory can be fixed, the overall problem of empirical falsification occurs. I then put forward my own theory, based on the modified Hobbesian theory. The major innovation is the replacement of individuals with groups in the Hobbesian State of Nature. This move answers the problem of empirical falsification, at least initially. The theory also helps to explain several of the more technical problems with Hobbes�s theory. The resulting theory is a Hobbesian theory of primitive state formation. The next step in the thesis is to match the Hobbesian theory of primitive state formation to the empirical evidence of primitive state formation, represented by anthropology. I analyse the anthropological literature and put forward that at least one recent research program in anthropology matches my Hobbesian theory of primitive state formation. I conclude that Hobbesian theory, based on the TCA can be successfully modernised into a plausible answer to the question of how primitive states formed.

Thesis (Ph.D.)--Indiana University, Dept. of English and American Studies, 2008.
Title from PDF t.p. (viewed on May 12, 2009). Source: Dissertation Abstracts International, Volume: 69-08, Section: A, page: 3153. Advisers: Purnima Bose; Margo N. Crawford.

This study was a comparative analysis of the highly structured legal systems of the state of Indiana and the United States of America and the unwritten legal systems of the Ashanti, Barotse, Buganda, and Nuer tribes of Africa. The purpose was to review the similarities and differences in the way in which those legal systems are structured, the way they function, and the scope of their impact on their respective societies.Complex societies have governmental entities which perform different functions in the legal system, but tribal societies tend to have people who perform multifunctional roles. The key is to observe the system to see what functions are being performed, and not to observe the system only to see if the same types of entities are performing the functions in simple societies as in complex societies.The “law is whatever is needed in a particular society. Dispute resolution must be accomplished, but the absence of a formal system does not mean the there is absence of law.
Department of Anthropology

The main objectives of this study were to identify the role that customary law and traditional leadership can play, without compromising their current positions or future recognition through legislation, in creating a better life for their constituents. The study analysed diverse issues such as legislative reform, the future role and functions of traditional leaders, training needs of traditional leaders, and the impact of a possible lack of commitment by national and provincial government on the training of traditional leaders to fulfill their functions within the ambit of the Constitution.

Thesis (Ph. D.)--University of California, San Diego, 2010.
Title from first page of PDF file (viewed February 17, 2010). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 253-268).

The general purpose of this thesis is to provide a gendered analysis of the ways in which States use their power to facilitate and promote accumulation, specifically primitive accumulation. I will seek to demonstrate in this study that women, classed and racialised, and especially those migrating within the neo-liberal global political economy are exploited not only through the classical alienation of their labour, but from the application of the additional extra-economic power of patriarchy and the tools that provides to states, and typically male owning classes. Women&rsquo
s position in patriarchal society and patriarchal capitalism may transform their experiences with capital and the state into a relationship of accumulation by dispossession rather than having their labour alienated and exploited under typical expanded reproduction. States use the constructions of women as subordinate under patriarchy, as well as others about migrant labour, or about the &lsquo
aberrant&rsquo
nature of sex work, to justify the use of women&rsquo
s bodies in the sex trade in a way that promotes the primitive accumulation, or accumulation by dispossession of surplus value from their labour and bodies. This study will use the Turkish Republic of northern Cyprus as an example to highlight the arguments made about the ability of a patriarchal state in collusion with capital, to use the extra controls afforded by patriarchy to primitively accumulate wealth from women, and to reproduce that ability on a continuous scale.

A civilização minóica da Creta da Idade do Bronze foi uma das poucas civilizações européias a organizar a sociedade através de um sistema palacial. Os estudos sobre a formação dos estados minóicos devem analisar em profundidade o sistema administrativo palacial e as mudanças no mesmo ao longo de seus seis séculos de funcionamento - neste trabalho pretende-se analisar a evolução da complexidade das unidades sócio-políticas minóicas através da análise de suas formas administrativas. A definição de categorias de sítios administrativos - pela análise funcional dos vestígios arquiteturais e dos achados arqueológicos dos mesmos - e o estudo dos padrões hierárquicos entre os diversos sítios, serão o cerne do trabalho. O uso de metodologias apropriadas para a análise de processos de mudança e formação de instituições político-administrativas, como a Teoria de Sistemas e os conceitos de peer polity interaction de Colin Renfrew, serão as ferramentas básicas deste projeto. Esse trabalho é um desdobramento de pesquisa desenvolvida em Mestrado realizado no MAE/USP sobre as interações entre os estados primitivos de Creta e as práticas de culto minóicas.
The Minoan Civilization of the Bronze Age Crete was one of the few european civilizations that organized its society through a palatial system. The studies about the development of the Minoan States must analyse thoroughness the administrative palatial system and the changes that have occured on it during its six centuries of functioning. In this thesis we intend to analyse the complexity evolution of the Minoan polities through the analysis of its administrative configurations. The definition of administrative sites - through the function analysis of the architectural vestiges and of its archaeological discoveries - and the study of the hierarchic patterns among the sites, will be the main point of this research. The use of usefull methodologies for the analysis of early state formation and culture change, like systems theory and the concepts of peer polity interaction, will be the basis tools of this project. This research follows research developed in the mastership done in MAE/USP about the interaction between the early states of Crete and the Minoan ritual practices.

Au cours de la préimplantation, l'embryon de souris produit deux lignages cellulaires, le trophectoderme (TE), et la masse cellulaire interne (MCI) qui elle-même se différencie en épiblaste (Epi) et en endoderme primitif (EPr), caractérisés respectivement par l'expression exclusive de Nanog et de Gata6. La voie FGF/MAPK joue un rôle critique dans l’acquisition de l’identité EPr. J’ai examiné l’expression de pERK, DUSP4 et ETV5 qui permettent de visualiser l'activité des MAPK. Ces analyses ont été effectuées en activant ou inhibant la voie FGF/MAPK, ainsi que dans des embryons mutants pour Nanog et/ou Gata6. Ceci a permis d’observer l’activation de la voie FGF/MAPK dès E3,25. Un autre volet de mon travail a été d'analyser la voie de l’IGF dans les embryons préimplantatoires afin de comprendre l’influence de cette voie dans les différents lignages. J’ai montré que le récepteur activé pIGF1R est exprimé de manière différentielle dans le TE, l’EPr et l’Epi au cours du développement. Une supplémentation d’IGF1 induit une augmentation du nombre de cellules en deux phases, d'abord de l’Epi puis de l’EPr. A l’inverse, une perte de fonction d’IGF1R induit une diminution du nombre de cellules entre E3,75 et E4,25
During preimplantation, mouse embryo produces two cellular lineages, the trophectoderm (TE), and the inner cell mass (ICM), which differentiates in epiblast (Epi) and primitive endoderm (PrE), characterized respectively by the complementary expression of Nanog and Gata6. FGF/MAPK pathway plays a critical role in the acquisition of a PrE identity. I examined the expression of the markers of MAPK activity pERK, DUSP4 and ETV5. The analyze was performed with activation or inhibition of FGF/MAPK pathway and in mutant embryos for Nanog or Gata6. This showed that FGF/MAPK pathway is activated as soon as E3,25. I have also analyzed the IGF pathway in preimplantation embryos in order to understand the role of this pathway in embryonic lineages. I showed that active receptor pIGF1R is differentially expressed in TE, PrE and Epi during embryonic development. Supplementation with IGF1 induces an increase in cell number in two phases, first in Epi then in PrE. Conversely, loss of function of IGF1R induces a decrease in cell number between E3,75 and E4,25

L'Archéen, de 4 à 2,5 Ga, est la période qui a connu les plus grands bouleversements géologiques et biologiques de l'histoire de la Terre : formation des continents, transition d'une tectonique à composante verticale vers une tectonique des plaques horizontale, apparition de la vie, ... Le but de cette thèse est d'étudier les conditions environnementales de la Terre à l'Archéen, par l'analyse des compositions isotopiques de métaux de transition (Fe, Zn) de roches provenant principalement de la province d'Isua au Groenland (3,8 Ga). Après avoir adapté le protocole de séparation du Fe, Cu, Zn à des échantillons riches en Fe, nous avons acquis les données par spectrométrie de masse à source plasma et à multicollection MC-ICPMS. Nous nous sommes d'abord intéressés au processus de serpentinisation de la croûte océanique, réaction produisant à la fois des nutriments pour la vie (CH 4 , H 2 ) et des minéraux catalyseurs (mackinawite) de la formation abiotique d'acides aminés, molécules du vivant. L'affleurement d'Isua comporte une unité ophiolitique présentant les serpentinites les plus anciennes (3.81-3.70 Ga) : leur analyse permet d'appréhender la réaction de serpentinisation à l'Archéen. Les résultats obtenus pour la composition isotopique du zinc dans ces roches et dans des serpentinites modernes ont permis d'établir une correspondance entre le processus de serpentinisation à Isua et la mise en place de volcans de boues de serpentinites à l'aplomb de la fosse des Mariannes. Nous avons ainsi pu identifier Isua comme une zone d'arrière-arc de subduction océanique, lieu d'une serpentinisation produisant des fluides de température variable (100-300°C) et de pH alcalin (9-12). Nous montrons que cette configuration atypique réunissant serpentinisation, fluides alcalins et édifices volcaniques est favorable à l'émergence du vivant. Nous avons ensuite analysé de nombreux échantillons de formations de fer rubané (BIFs), sédiments propres à l'Archéen et au début du Protérozoïque. L'évolution de la composition isotopique du zinc de ces échantillons au cours du temps a permis d'établir une chronologie de l'émersion des continents.Nos résultats sont en faveur d'une émersion débutant il y a 2,9 Ga. Enfin, nos données nous informent sur la colonisation des continents émergés par la vie à 2,6 Ga et sur la pédogenèse de sols archéens comportant un horizon organique.

This research aimed to undertake an investigation into the question of whether after divorce, in the matrilineal customary law marriage in Malawi, women's rights are severely violated. The study showed causes of divorce, how proceedings are done, how issues of property are handled, how the issue of custody of children and maintenance are also handled. All this was weighed against the constitutional provisions and international law.

L'hematopoiese est un processus dynamique qui assure le renouvellement continuel de grandes quantites de cellules sanguines matures, a partir d'un compartiment restreint de cellules souches et de progeniteurs indifferencies. Un reseau de regulation complexe integrant des signaux a la fois positifs et negatifs intervient pour controler precisement cette production et maintenir l'homeostasie du tissu hematopoietique. En situation physiologique in vivo, les cellules les plus primitives du systeme hematopoietique sont principalement dans un etat de quiescence ou presentent une faible activite de division, malgre leur fort potentiel de proliferation. Le tgf-1 pour transforming growth factor-1 semble etre un bon candidat pour controler cet etat de quiescence. En effet, des alterations au niveau de sa voie de signalisation sont souvent associees a la transformation neoplasique de cellules hematopoietiques precoces. Cependant, les mecanismes par lesquels le tgf-1 controle le cycle cellulaire et le developpement des progeniteurs hematopoietiques restent incompletement caracterises. Une analyse des profils de dose-reponse au tgf-1 a ete realisee sur differents types de progeniteurs hematopoietiques, depuis le stade de progeniteur erythro-myeloide multipotent possedant un fort potentiel de proliferation jusqu'a celui de progeniteur plus tardif unipotent. Lorsque de tres faibles concentrations de tgf-1 sont utilisees (10-30 pg/ml), son effet anti-proliferatif est preferentiellement cible sur les progeniteurs les plus primitifs. De plus, l'utilisation d'anticorps bloquants diriges contre le tgf-1 lui meme (anti-tgf-1) ou contre son recepteur de type ii a la surface des cellules (anti-tr-ii) permet la mise en cycle d'une population cellulaire primitive non detectee dans un test de culture a court terme classique de 2 a 3 semaines. Suite a un traitement par un anti-tgf-1 ou un anti-tr-ii, ces progeniteurs, que nous appelons cellules hpp-q pour high proliferative potential-quiescent (hpp-q) cells, entrent dans une phase de division active et donnent naissance a des clones macroscopiques. Des etudes moleculaires ont montre que le tgf-1 maintient les cellules hpp-q dans un etat de faible activite mitotique via une modulation negative de l'expression de plusieurs recepteurs de cytokines (flt3, ril-6, mpl) a la surface des cellules, empechant ainsi une reponse rapide a leurs ligands respectifs (fl, il-6, tpo). Inversement, l'effet de l'anti-tgf-1 se traduit par une modulation positive de l'expression de ces recepteurs, ce qui accroit la sensibilite des cellules hpp-q aux facteurs de croissance mitogeniques. En plus de sa capacite a inhiber la proliferation des progeniteurs hematopoietiques primitifs, le tgf-1 semble ralentir leur engagement vers la differenciation. Nous avons en effet observe que, lorsqu'il est associe a une combinaison de facteurs de croissance stimulant non seulement la proliferation mais aussi la maturation, le tgf-1 augmente le niveau d'expression du marqueur d'immaturite cd34 a la surface des progeniteurs. De plus, il favorise le maintien d'une sous-population de cellules qui conservent un phenotype cd34 f o r t apres 3 a 4 divisions successives, alors qu'elles echappent a son effet anti-proliferatif. Ces resultats suggerent que le tgf-1 participe a la gestion de la reserve de cellules hematopoietiques primitives, en controlant de facon independante leur proliferation et leur etat d'immaturite.

Justification de l’étude. Les déficits immunitaires primitifs (DIP) sont caractérisés par une grande hétérogénéité clinique, biologique, génétique et thérapeutique. Très peu de connaissances sont disponibles quant au devenir à long terme des patients en termes d’état de santé et de qualité de vie. Objectif : L'objectif principal de l’étude est de mettre en place un dispositif capable d’étudier les déterminants du devenir à long terme d’une cohorte de patients présentant un diagnostic de DIP diagnostiqué au cours de leur enfance. Résultats. Au 1er juin 2016, 1014 patients ont été inclus dans la cohorte sur les 1800 interrogés. La cohorte adulte montre que l’état de santé est marqué par la prévalence très élevée d’évènements de santé sévère ou très sévères (touchant 87% des adultes), avec un taux de cancer de 7.6%. Comparé aux normes françaises, tous les domaines de qualité de vie sont significativement altérés. Seuls les patients greffés présentent une qualité de vie meilleure par rapport aux patients non greffés. Nous montrons que la QoL est inversement proportionnelle à la survenue de complications sévères. L’étude pédiatrique fait le même constat, démontrant que c’est très tôt pendant l’enfance que surviennent les complications sévères dont l’impact sur leur qualité de vie est majeur. Conclusion : les patients atteints de DIP présentent un état de santé marqué par une fréquence très élevée d’évènements de santé de haut grade, et ceci très précocement dans l’enfance. La lourdeur de leur état de santé est le déterminant principal de la mauvaise qualité de vie des patients, justifiant d’une prise en charge spécialisée et multidisciplinaires dès le diagnostic posé
Importance: Most children with primary immunodeficiencies (PID) now reach adulthood. Assessment of their long-term health status represents a major challenge. We aimed to gain insight into how PID affects patient health status and quality of life (QoL). Design: The French Reference Center for PIDs (CEREDIH) initiated a prospective multicenter cohort which enrolled participants who met all inclusion criteria: (1) patient with PID included in the CEREDIH registry, (2) clinical diagnosis before 18 years, (3) alive and living in France. Among 1810 patients eligible for inclusion (on 1/17/2016), 1047 were children, and 763 were adults. A severity score was assigned to each health condition: grade 1 (mild) to grade 4 (life-threatening/disabling). We report the health status of children by focusing on two endpoints: grade 4 conditions and grade 3 or 4 conditions. Results: In the adult study, only 12% of adults with PID had never experienced severe or life-threatening conditions, and 7.6% of patients had been diagnosed with cancer. Furthermore, adults reported significantly lower scores for all domains of QoL, and QoL was strongly associated with poor health conditions. In the pediatric study, the response rate was 62.5%. Of the 656 children participants, 83% experienced at least one grade 3 or 4 condition. Children with PID scored significantly lower for most QoL domains. QoL was strongly associated with heavy burden of health conditions. Conclusions: Taken together, these studies demonstrate that the deleterious health effects bore by patients with PID become heavy since childhood, emphasizing the need to establish multidisciplinary healthcare teams, from childhood

Les cellules souches hematopoietiques humaines sont la plupart du temps au repos, en phase g0/g1 du cycle cellulaire, mais possedent neanmoins un potentiel de proliferation et de differenciation tres important. Des donnees cellulaires et moleculaires montrent que le tgf-1 joue un role capital dans l'inhibition de l'activite mitotique de ces cellules. Notre laboratoire a montre que l'utilisation in vitro d'un anticorps anti-tgf- entraine la mise en cycle de ces cellules et revele des cellules tres immatures multipotentes, particulierement sensibles au tgf-1. Nous nommons ces cellules hpp-q pour high proliferative potential-quiescent cells. Les cellules hematopoietiques primitives sont des cibles de choix pour la therapie genique. En effet, un faible nombre de ces cellules peut potentiellement generer un grand nombre de cellules hematopoietiques differenciees portant et exprimant un gene exogene. Nous montrons que lors d'une infection retrovirale, ces cellules primitives expriment fortement et de maniere transitoire du tgf-1 endogene, empechant ainsi leur proliferation en culture in vitro. Nous proposons donc de bloquer l'effet anti-proliferatif du tgf-1 et d'utiliser le test hpp-q, test de culture clonale, pour reveler et quantifier rapidement, en 2 semaines, des cellules multipotentes ayant integre le transgene. Afin de mieux comprendre les mecanismes impliques lors de la reponse anti-proliferative du tgf-1 dans les cellules immatures hematopoietiques, nous avons etudie la modulation de l'expression de proteines qui controlent le cycle cellulaire. Nous montrons notamment que des sous-populations de cellules tres immatures (cd34 + cd38 -) expriment les arnm d'inhibiteurs de la phase g0/g1, tels que p27, ou p16. De plus, nous avons mis en evidence par hybridation in situ, que l'arnm de p21, inhibiteur de la famille cip/kip, est regule par du tgf-1 endogene dans des progeniteurs hematopoietiques cd34 +. P21 intervient donc dans la voie de signalisation du tgf-1 lors de la regulation des stades precoces de l'hematopoiese.

Thesis (M. Tech.) -- Central University of Technology, Free State, 2007
The lack of a standardized lighting instrument to be used in conjunction with existing photographic methods to document rock art, is a problem experienced in archaeological circles. Through interviews with archaeologists and an investigation into existing photographic methods concerning the photographing of rock art, a demand for a portable and modular lighting instrument was confirmed. The aim of this study, then, was to develop a prototype lighting instrument to fill this void. The design and manufacture of the modular lighting instrument entailed the harnessing of the technological advances made in the field of rapid prototyping. A brief overview of the San/Bushmen of Southern Africa is given to stress the importance of this study and to emphasise the importance of the art of the Bushman in our collective art heritage. An overview of the documenting of rock art and therewith an investigation into documented works of rock art and rock engravings by the San/Bushmen serves as a point of departure for the present inquiry. Tests undertaken with the modular lighting instrument, and a comparison of the results so obtained with existing photographic methods, showed that with the use of the modular lighting instrument, an improvement in illumination, rock-face texture and colour contrast in the images was obtained. The modular lighting instrument helps to create and regulate a suitable lighting environment irrespective of natural lighting circumstances and environments. It produces better results when it comes to documenting rock art in comparison to existing methods of documentation. Continued study for the development of the modular lighting instrument is recommended in order to produce more constant results.

Les abondances en éléments sidérophiles du manteau terrestre indiquent une ségrégation du noyau dans un océan magmatique profond. Il est néanmoins difficile de contraindre les conditions d’oxydation prévalant lors de l’accrétion planétaire, en se basant sur les traceurs géochimiques, en raison du nombre important de paramètres qui affectent leurs partages entre métal et silicate. D’autre part, l’état d’oxydation des planètes peut évoluer au cours de l’accrétion. Par conséquent, la nature des matériaux accrétés lors de la formation des planètes reste incertaine. Afin d’apporter de nouveaux éléments de réponses à cette problématique, nous avons modélisé les équilibres chimiques ayant lieu dans la Terre primitive. Ces équilibres peuvent évoluer (i) en augmentant les conditions de pression et de température de la ségrégation du noyau lors de la croissance de la planète, (ii) en raison de la cristallisation de l’océan magmatique et (iii) à travers l’accrétion de matériaux hétérogènes de compositions et états redox différents. Nous avons exploré le rôle potentiel de l’érosion collisionnelle dans le contexte de l’accrétion de la Terre à partir de chondrites à enstatite. Pour cela, nous avons déterminé expérimentalement les compositions chimiques des liquides pseudo-eutectiques en fonction de la pression jusqu’à 25 GPa. Nous avons montré que ces premiers liquides sont très enrichis en SiO2 (jusqu’à 75 wt% SiO2) et en éléments alcalins (Na et K). Par conséquent, l’érosion collisionnelle de proto-croutes de planétésimaux formés de chondrites EH peut de manière efficace augmenter le rapport final Mg/Si du manteau terrestre et réduire ses concentrations en éléments alcalins volatils. Ce mécanisme peut donc concilier les différences compositionnelles entre la Terre et les chondrites à enstatite. Nous avons également déterminé expérimentalement le partage du soufre entre métal riche en fer et silicate. La concentration en soufre du manteau terrestre peut être expliquée par un équilibre entre manteau et noyau dans un océan magmatique profond. L’hypothèse de l’ajout de soufre dans un vernis tardif (Rose-Weston et al., 2009) n’est pas à exclure, mais il n’est pas indispensable pour atteindre la concentration en soufre du manteau. Ces résultats sont en accord avec les compositions isotopiques non chondritiques du soufre dans le manteau (Labidi et al., 2013). Le partage des éléments légers (S, Si, O) entre manteau et noyau a été modélisé à hautes pressions et températures en prenant compte de leurs interactions chimiques mutuelles et celles avec le carbone. En considérant 2 wt% S et jusqu’à 1.2 wt% C (comme il est suggéré par les études cosmochimiques), nous trouvons une solubilité de l’O comprise entre 1 et 2.4 wt%. Cette insertion de l’O dans le noyau n’est pas suffisante pour permettre à la Terre d’être à la fois accrétée de matériaux météoritiques oxydés et de posséder un noyau métallique d’une masse équivalente au tiers de la planète ainsi que 8 wt% FeO dans le manteau. Des conditions relativement réduites lors de la ségrégation du noyau sont également requises pour augmenter le taux de Si dans le noyau et expliquer le rapport Mg/Si super-chondritique de la Terre silicatée (Allègre et al., 1995; O’Neill et al. 1998). Ainsi, la Terre s’est plus probablement accrétée à partir de matériaux réduits comme les chondrites à enstatites, conduisant à un noyau constitué de 2 wt% S, 0 à 1.2 wt% C, 1 wt% O et 5.5 à 7 wt% Si. Nous avons également exploré le comportement du Fe lors de la cristallisation de la pérovskite magnésienne (le minéral le plus abondant du manteau terrestre) et son rôle sur l’état redox du manteau terrestre lors du refroidissement de l’océan magmatique. Nous avons montré que sa cristallisation induit une diminution du FeO dans le manteau solide, lors d’un équilibre avec un alliage de fer liquide à une fO2 de IW-2 en raison du caractère incompatible du Fe dans la pérovskite. (...)
Abundances of siderophile elements in the mantle indicate that the Earth’s core segregated in a deep magma ocean. Yet, it is unfortunately difficult to constrain the oxidation conditions prevailing during planetary accretion based on geochemical tracers due to the number of parameters playing a role in metalsilicate partitioning. In addition, the oxidation state of terrestrial planets can evolve during accretion. The nature of the accreted material during the formation of the terrestrial planets remains then still uncertain. Our strategy to improve our knowledge in this domain is to model the chemical equilibria taking place in the primitive Earth. The equilibria can evolve (i) as P-T conditions of core-mantle segregation increase with the size of the planet, (ii) due to crystallization of the magma ocean and (iii) with accretion of heterogeneous material of different composition and oxidation state. We explored the potential role of collisional erosion in the context of Earth’s accretion from Enstatite Chondrites. For this, we refined experimentally the chemical composition of pseudo-eutectic melts as a function of pressure up to 25 GPa. We show that the first melts are highly enriched in SiO2 (up to 75 wt% SiO2) and alkali elements (Na and K). Therefore, collisional erosion of proto-crusts on EH-planetesimals can efficiently increase their final Mg/Si ratio and decrease their alkali elements budget. It can help to reconcile compositional differences between bulk silicate Earth and Enstatite Chondrites. We performed new experiments on metal-silicate partitioning of sulphur. We show that the present-day sulphur concentration of the Earth’s mantle can be explained by core-mantle equilibration in a deep magma ocean. S-addition in a late veneer (Rose-Weston et al., 2009) cannot be excluded; however, it is not required in order to reach the S-mantel abundance. Our results are consistent with the non-chondritic S-isotopic nature of the mantle (Labidi et al., 2013). We modeled the core-mantle partitioning of the light elements (S, Si, O) at high pressures and temperatures, by taking into account of their mutual chemical interactions and that with C. With 2 wt% S in the core and a C concentration ranging 0 to 1.2 wt% (as evidenced with cosmochemical studies), we found the O solubility from 1 to 2.4 wt%. This O incorporation to the core is insufficient to both allow an Earth accretion from an oxidized meteoritic material and result in a planet composed of a core with a mass equivalent to the third of its mass and a mantle with 8 wt% FeO content. Reduced conditions during coremantle segregation are also required to enhance the Si content in the core, possibly up to 5 wt% Si, to explain the super chondritic Mg/Si of the bulk silicated Earth (Allègre et al., 1995; O’Neill et al. 1998). Altogether, we find that the Earth was most likely accreted from a reduced material, such as enstatite chondrites, leading to a core composed of 2 wt% S, 0 to 1.1 wt% C, 1 wt% O and 5.5 to 7 wt% Si. We investigated the role of Mg-perovskite (the most abundant mineral of the mantle) crystallization on the oxidation state of Earth’s mantle during cooling of the magma ocean. We show that its crystallization induces a decrease of FeO content of the solid mantle as Fe is incompatible in perovskite, when it is in equilibrium with a liquid Fe-alloy at an fO2 of IW-2. At these conditions, the Fe3+ insertion is also low and constant (Fe3+/ Fetot of 21 ±4 %). Hence, the Mg-Pv crystallization cannot be responsible for a substantial increase of the Earth’s mantle oxygen fugacity during core segregation. (...)

This thesis draws on David Harvey’s concept of “accumulation by dispossession” and an international political economy (IPE) approach centred on the institutional arrangements and power structures that privilege certain actors and values, in order to critique current capitalist practices of primitive accumulation by the global corporate extractive industry. The thesis examines how accumulation by dispossession by the global extractive industry is facilitated by the “free entry” or “free mining” principle. It does so by focusing on Canada as a leader in the global extractive industry and the spread of this country’s mining laws to other countries – in other words, the transnationalisation of norms in the global extractive industry – so as to maintain a consistent and familiar operating environment for Canadian extractive companies. The transnationalisation of norms is further promoted by key international institutions such as the World Bank, which is also the world’s largest development lender and also plays a key role in shaping the regulations that govern natural resource extraction. The thesis briefly investigates some Canadian examples of resource extraction projects, in order to demonstrate the weaknesses of Canadian mining laws, particularly the lack of protection of landowners’ rights under the free entry system and the subsequent need for “free, prior and informed consent” (FPIC). The thesis also considers some of the challenges to the adoption and implementation of the right to FPIC. These challenges include embedded institutional structures like the free entry mining system, international political economy (IPE) as shaped by international institutions and powerful corporations, as well as concerns regarding ‘local’ power structures or the legitimacy of representatives of communities affected by extractive projects. The thesis concludes that in order for Canada to be truly recognized as a leader in the global extractive industry, it must establish legal norms domestically to ensure that Canadian mining companies and residents can be held accountable when there is evidence of environmental and/or human rights violations associated with the activities of Canadian mining companies abroad. The thesis also concludes that Canada needs to address underlying structural issues such as the free entry mining system and implement FPIC, in order to curb “accumulation by dispossession” by the extractive industry, both domestically and abroad.

碩士
國立交通大學
資訊工程系所
94
Structural correctness and resource allocation are two major topics of workflow researches, but few researchers are interested in artifact analysis. A workflow execution may fail because of incorrect structures or resource conflict. On the other hand, inaccurate artifact manipulation will bring some problems during workflow execution too, e.g., inconsistency between data flow and control flow, contradictions between artifact operations…, etc. The thesis studies a model, compatible with most models for specifications, and thus a simple methodology for validating the use of artifacts. In the model, we also present a bottom-up workflow design method based on artifact operations. The concept of state transitions for artifacts is adopted to construct six types of artifact inaccuracy impacting on workflow execution, and inaccuracy detection algorithms in order to validate artifact usages in workflow specifications.

We initiate the study of a new class of semigroup C*-algebras arising from number-theoretic considerations; namely, we generalize the construction of Cuntz, Deninger, and Laca by considering the left regular C*-algebras of ax+b-semigroups from actions of congruence monoids on rings of algebraic integers in number fields. Our motivation for considering actions of congruence monoids comes from class field theory and work on Bost–Connes type systems. We give two presentations and a groupoid model for these algebras, and establish a faithfulness criterion for their representations. We then explicitly compute the primitive ideal space, give a semigroup crossed product description of the boundary quotient, and prove that the construction is functorial in the appropriate sense. These C*-algebras carry canonical time evolutions, so that our construction also produces a new class of C*-dynamical systems. We classify the KMS (equilibrium) states for this canonical time evolution, and show that there are several phase transitions whose complexity depends on properties of a generalized ideal class group. We compute the type of all high temperature KMS states, and consider several related C*-dynamical systems.
Graduate

Tese de mestrado, Biologia Humana e Ambiente, Universidade de Lisboa, Faculdade de Ciências, 2021
A pluripotência é definida como o potencial de gerar todas as linhagens celulares presentes no organismo adulto, com três estados distintos identificados. Recentemente descrito, o estado de pluripotência roseta é um estado reversível, intermédio entre os já estabelecidos estados naïve e primed, associados in vitro às células estaminais embrionárias (ESC) e células estaminais do epiblasto, respectivamente. In vivo, este estado intermédio associa-se às células do botão embrionário, na fase de peri-implantação do embrião, onde ocorre uma polarização e reorganização das células naïve numa roseta embrionária. As células estaminais roseta (RSC), já derivadas e sustentadas em culturas in vitro com recurso à inibição da sinalização Wingless-INT (Wnt) e proteína-quinase quinase ativada por mitógenos (MEK), têm o seu próprio perfil biológico. Uma das características especifícas das RSCs é a co-expressão do fator naive Klf4 e do fator primed Otx2. Apesar do estado de pluripotência roseta estar já a ser caracterizado, ainda pouco se sabe relativamente à sua biologia. Com este estudo, o nosso foco assentou em aprofundar o conhecimento deste novo estado de pluripotência, através da caracterização das RSCs. Para isto, selecionámos processos biológicos que ocorrem, in vivo, no embrião na fase de pré-implantação. Nestes processos, comparando com a resposta das ESCs de Mus musculus sujeitas aos mesmos protocolos, testámos a resposta das RSCs de forma a observar se haveria uma alteração no seu potencial de desenvolvimento. Um dos processos biológicos analisado foi a diferenciação de endoderme primitiva, uma das três linhagens celulares que se encontram no blastocisto de ratinho, tendo início no botão embrionário a E3.5. A capacidade das RSCs (e incapacidade das células estaminais do epiblasto) em derivar endoderme primitiva tinha já sido demonstrada em estudos prévios, através de diversos modelos in vitro. De modo a tornar a nossa abordagem mais robusta, utilizámos uma linha celular repórter Gata6::GFP, o primeiro marcador génico de endoderme primitiva a ser expresso. Adaptámos dois distintos e previamente publicados protocolos de diferenciação desta linhagem - a duas dimensões e através da formação de corpos embrióides - com recurso a fatores de indução. Os nossos resultados demonstraram que, quando submetidos ao processo de diferenciação, tanto as ESCs como as RSCs apresentam um aumento da expressão de marcadores génicos da endoderme primitiva. No entanto, o processo de diferenciação por formação de corpos embrióides revelou que no caso das RSCs, o marcador Gata6 é significativamente menos expresso. Este resultado sugere que a capacidade de diferenciação destas células em endoderme primitiva está comprometida, sendo significativamente menos eficiente. O outro processo abordado, a diapausa embrionária, refere-se a um estado de dormência celular reversível no período de pré-implantação, que consiste na suspensão do crescimento embrionário. Este processo foi descrito em diversas espécies animais, incluíndo Mus musculus, como uma estratégia para evitar condições desfavoráveis no momento do parto. In vitro, o processo descrito foi já mimetizado através da utilização de inibidores de Myc e mTOR. Estes permitem que as ESCs entrem num estado semelhante ao que ocorre in vivo, observando-se uma diminuição no splicing, na transcrição e síntese proteica. Simultaneamente, ocorre uma redução acentuada da proliferação e consequente dormência celular. Os nossos resultados, utilizando estes mesmos inibidores indutores de diapausa, revelaram uma diferença na resposta entre as ESCs e as RSCs. Foi observada uma supressão superior a nível da expansão celular nas RSCs, que aqui sugerimos dever-se a um aumento da morte celular destas quando induzidas em diapausa, mantendo, no entanto, o seu potencial pluripotente após recuperação deste processo. Com base nos resultados obtidos, sugerimos que as RSCs apresentam uma capacidade reduzida para entrar num estado de diapausa. A acrescentar aos processos biológicos já mencionados, focámo-nos também num outro ponto essencial no desenvolvimento embrionário. As alterações metabólicas ao longo da progressão da pluripotência foram já descritas como fundamentais para a transição celular. No estado naive, as células apresetam um metabolismo misto com respiração mitocondrial e atividade glicolítica, passando para um metabolismo exclusivamente glicolítico no estado primed. Como tal, considerando os perfis metabólicos associados a distintos estados de pluripotência, analisámos os níveis de fosforilação oxidativa das RSCs, comparando com as ESCs. Os nossos resultados demonstraram diferenças entre os dois tipos celulares, apresentando as RSCs uma taxa de consumo de oxigénio geral mais baixa, que se traduz em níveis mais baixos de respiração mitocondrial. Esta tendência é também observada em células primed e está associada a um estado de pluripotência mais avançado. Neste trabalho identificámos respostas distintas das RSCs, em comparação com as ESCs, ao nível de processos de desenvolvimento embrionário e ao nível do perfil metabólico destas células, reveladoras dos seus estados de pluripotência distintos. Com isto, pretendemos aprofundar a caracterização particular do estado de pluripotência roseta, de modo a acrescentar ao conhecimento presente referente ao contínuo da progressão da pluripotência.
Pluripotency is defined as the potential to form all cell lineages present in the adult organism, with three different stages identified., The rosette pluripotent stage is a novel reversible pluripotent state, intermediate between the naïve and primed stage. This stage is associated to developmental period of the peri-implantation epiblast - where the naïve cells polarize and rearrange in an embryonic rosette. Rosette stem cells, correspondent to this state in vitro, have their own individual biological profile, showing a characteristic co-expression of the naïve factor Klf4 and primed factor Otx2. Little is known about the biological status of the rosette stage. With this study we focused providing a deeper biological knowledge and characterization of rosette stem cells, concretely through the comparison with the naïve stage embryonic stem cells. For this purpose, we selected biological processes in which the behavior of the naïve cells has previously been described and tested the response of rosette stem cells, to observe if there is a change in developmental potential. Primitive endoderm differentiation is a process that starts developing in vivo in the inner cell mass of the blastocyst, at E3.5. Our data revealed a significant difference when comparing both cell types. The adaptation of two in vitro differentiation protocols revealed that while both cell types show an increase in the expression of primitive endoderm markers, in the case of rosette stem cells, Gata6 is less expressed. This suggests that the differentiation of these cells into primitive endoderm is significantly less efficient. We then assessed the ability of the cells to enter diapause, a dormant reversible state of the pre-implantation epiblast. The results revealed a difference between both cell types in the response to diapause-inducing inhibitors. Rosette stem cells showed a bigger suppression in cell expansion that we here suggest being caused by increased cell death, while retaining their pluripotent potential after recovery. Furthermore, and considering the importance of the metabolic shift for pluripotency progression and the previously established distinct metabolic profiles for naïve and primed pluripotent cells, we analyzed the oxidative phosphorylation levels of rosette stem cells. We observed that, in comparison to embryonic stem cells, these cells possess an overall lower oxygen consumption rate that translates in lower levels of mitochondrial respiration. This trend is also observed in primed cells. Our work indicated differences in, not only the response to developmental processes, but also in the metabolic profile between embryonic and rosette stem cells. With this, we aim to specify the particular characteristics of the novel rosette pluripotent state, improving our knowledge on the continuum that is pluripotency progression.

Thesis (Ph.D.) -- Griffith University, 1998.
Restricted until 9th December, 1999. Digital copy of the author's original dissertation. Title taken from PDF title screen (viewed July 1, 2009). Includes bibliographical references.