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Engineering, expression and cytological effect of recombinant HGFbChen, Yi-Ting 17 August 2007 (has links)
Hepatocyte growth factor (HGF), a factor which stimulates cell growth, morphogenesis and migration, was found in hepatocytes and other epithelial cells. HGF was found to induce cell scattering, so that it was previously named as ¡§scatter factor¡¨ (SF), which turned out to be the same protein. HGF has two chains, a-chain, which contains N-terminal domain and four kringle domains and b-chain, a serine protease-like domain linked with a-chain by disulfide bond. The size of b-chain is 34 kDa after glycosylation in human cells. The function of HGFb was not unknown until recently that HGFb was shown 1000-fold lower affinity to c-Met than HGFa. Thus this project is to create biotechnological approaches for quick and large scale production of HGFb. The DNA fragment amplified by PCR was transferred to pET-22b(+) for expression, and showed that large amount of recombinant HGFb was produced both in periplasmic space and culture supernatant. Assays for cancer proliferation and migration with the HGFb showed that the recombinant protein inhibited cancer cells in a dose-independent manner. Our experiment showed clearly that 10 nM of the E. coli-produced HGFb inhibited proliferation and migration of cancer cells in comparison with the medium and pET controls, 1000-fold higher affinity to c-Met than reported.
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Arbetskraftsmigration, arbetsgivarmakt och mänskliga rättigheterCalleman, Catharina January 2011 (has links)
No description available.
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Migration of olfactory ensheathing cells grafted into adult rat spinal cordSkihar, Viktor 01 December 2004
Olfactory ensheathing cells (OECs) are non-myelinating glial cells that provide ensheathment for axons of the olfactory nerve in vivo. OECs have been shown to facilitate the regeneration of CNS axons, to assemble a myelin sheath around demyelinated axons, and it has been suggested OECs migrate very well within the microenvironment of the injured CNS. However, there has been no direct test of their migratory ability in vivo. The aims of this study were to determine whether: 1) OECs can be induced to migrate towards an ethidium bromide (EtBr)-induced focal (~1 mm long) demyelination of the spinal cord white matter; 2) OECs migrate away from a focal demyelination either into normal CNS tissue or towards a second demyelinated lesion; 3) microglial reactivity is required for the generation of the migratory signal(s) inducing OECs to migrate towards a focal demyelination; 4) OECs grafted into the subarachnoid space surrounding the spinal cord will migrate into the neuropil in the absence of demyelination.
To achieve these aims, we developed an in vivo model for studying the migratory ability of OECs within the adult rat spinal cord. A small focal EtBr-induced demyelination of the dorsal funiculus (unilaterally) of the spinal cord was made at variable distances from the site of a DiI-labelled OEC graft. The major findings were: i) the strength of the migratory signal(s) inducing OECs to migrate increased as the demyelinated lesion was located closer to the grafting site; ii) the OEC migration towards a distal demyelinated lesion was greatly enhanced when the cells were grafted directly into a second demyelinated lesion; iii) the cell migration occurred along a migratory path containing many reactive astrocytes and microglia; iv) the migration of OECs was significantly reduced when the microglial reactivity was dampened using minocycline; and v) OECs survived grafting into cerebrospinal fluid (i.e. subarachnoid space) and migrated into the neuropil of the brain and spinal cord. The major conclusions are that OECs can respond to migratory signal(s) arising as a result of a focal EtBr-induced demyelination and that microglia are one potential source of these migratory signal(s).
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A study of movement and order : the securitization of migration in Canada and FranceBourbeau, Philippe 11 1900 (has links)
This dissertation is about the movement of people and the system of order
underpinning the movement. In undertaking a comparative study of Canada and France
between 1989 and 2005, the study explores a widespread phenomenon that security
studies and migration scholars would have considered an anomaly only two decades ago:
understanding the movement of people as an existential security threat.
How is it that nation-states around the globe are cracking down on migration for
security reasons? How do we know if migration has been securitized - and which criteria
should we employed to guide our analysis? What are the social mechanisms at play in the
interaction between movement and order? Does a variation in levels of securitized
migration exist - and if so, what are the key determinants of the variation? These
questions are at the heart of the present study.
My argument is twofold. First, I contend that a constructivist perspective is useful in
gaining a better understanding of the social mechanisms involved in the securitization of
migration as it highlights discursive power, ideational factors, and cultural/contextual
elements. Second, I argue that securitization theory - the current benchmark in
securitization research - remains silent on the issue of variation in levels of securitized
migration. As such, securitization theory, as currently applied and organized, cannot
explain empirical findings of my study - a weak securitization in Canada versus a strong
securitization in France. Underscoring the necessity to amend securitization theory, I
investigate the impact of cultural factors - and especially the role of domestic audience -
to account for the variation.
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The Motivation of Long-Stay Tourism and International Retirement Migration: Swedish retirees in Thailand.Kummaraka, Krit, Jutaporn, Rapee January 2011 (has links)
Date: May 25, 2011 Program: MIMA-International Marketing Course name: Master Thesis (EFO705) Title: The Motivation of Long-Stay Tourism and InternationalRetirement Migration: Swedish retirees in Thailand. Authors: Mr. Krit Kummaraka (kka10003@student.mdh.se)Mr. Rapee Jutaporn (rjn10001@student.mdh.se) Supervisor: Mr. Peter Selegård Research Question: Which factors affect to the attitude for decision making ofretirement Swedish people to do as a long-stay tourism or Swedishretirement migration in Thailand? Purpose: The objective of this study is to describe and analyze the factorsthat affect to the attitude of Swedish people for making a decisionto do as a long-stay tourism or Swedish retirement migration inThailand. Method: This research is mainly based on qualitative research usingsurvey method. The main conceptual frameworks is “consumerdecision framework”. The datacollection is categorized into two sources: primary data andsecondary data. Conclusion: From our study, we learn that Swedish retirees have positiveattitude in Thailand. They have desire to migrate into Thailand. Allof eight element in consumer decision marking are effect to theirdecision, especially, the “motivation/ energizers” and “socioeconomicinfluence” factor. Key words: Consumer Attitude, Social Economic, Consumer Behavior, Long-Stay Tourism AND/OR Retirement Migration Influence inThailand
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Migration of olfactory ensheathing cells grafted into adult rat spinal cordSkihar, Viktor 01 December 2004 (has links)
Olfactory ensheathing cells (OECs) are non-myelinating glial cells that provide ensheathment for axons of the olfactory nerve in vivo. OECs have been shown to facilitate the regeneration of CNS axons, to assemble a myelin sheath around demyelinated axons, and it has been suggested OECs migrate very well within the microenvironment of the injured CNS. However, there has been no direct test of their migratory ability in vivo. The aims of this study were to determine whether: 1) OECs can be induced to migrate towards an ethidium bromide (EtBr)-induced focal (~1 mm long) demyelination of the spinal cord white matter; 2) OECs migrate away from a focal demyelination either into normal CNS tissue or towards a second demyelinated lesion; 3) microglial reactivity is required for the generation of the migratory signal(s) inducing OECs to migrate towards a focal demyelination; 4) OECs grafted into the subarachnoid space surrounding the spinal cord will migrate into the neuropil in the absence of demyelination.
To achieve these aims, we developed an in vivo model for studying the migratory ability of OECs within the adult rat spinal cord. A small focal EtBr-induced demyelination of the dorsal funiculus (unilaterally) of the spinal cord was made at variable distances from the site of a DiI-labelled OEC graft. The major findings were: i) the strength of the migratory signal(s) inducing OECs to migrate increased as the demyelinated lesion was located closer to the grafting site; ii) the OEC migration towards a distal demyelinated lesion was greatly enhanced when the cells were grafted directly into a second demyelinated lesion; iii) the cell migration occurred along a migratory path containing many reactive astrocytes and microglia; iv) the migration of OECs was significantly reduced when the microglial reactivity was dampened using minocycline; and v) OECs survived grafting into cerebrospinal fluid (i.e. subarachnoid space) and migrated into the neuropil of the brain and spinal cord. The major conclusions are that OECs can respond to migratory signal(s) arising as a result of a focal EtBr-induced demyelination and that microglia are one potential source of these migratory signal(s).
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Casualties among Unauthorized Migrants at the Arizona Border : A Race, Class and Gender PerspectiveHällgren, Linnea January 2012 (has links)
This bachelor thesis deals with the increasing borders control/security between nations, especially between the, so-called third world and first world nations. Security and wall building is something that is becoming a more and more current issue at borders. Today we live under the scare of terrorism which excuses this behavior. The state seeks to gain more control over whom they are letting in. This has, created harsher laws for immigration, and especially unauthorized such, creating a global apartheid and mistreatment of unauthorized migrants. This study focuses on unauthorized migration and especially on the casualties of such attempts to cross the border betweenMexicoandArizonacaused by walking through the Sonoran desert. The United States has during the 90’s and this the 2000’s deliberately been pushing unauthorized migration routes further from urban areas out in to remote desert in order to discourage it. This has led to a rising number of deaths among unauthorized migrants trying to cross into theUnited StatesfromMexicoand other Latin American countries. This bachelor thesis focuses on the statistics taken from border patrol reports that were listed in the newspaper the Arizona Daily Star. It also contains an interview made with a volunteer from the organization No More Deaths/No Mas Muertes, an organization working for the prevention of deaths in the Sonoran desert and more human immigration policies. A perspective of this bachelor thesis is also gender: how these policies affect gender, and whether women who migrate unauthorized are exposed to more risks than men. The conclusion of the essay is that the majority who migrate unauthorized are male. The women who migrate, however, are exposed to more risks. They are more prone to travel with family or children making them more vulnerable due to the extra responsibility. Traveling alone, they are more vulnerable to sexual assaults. Sexual assaults can come from coyotes, other migrants and border patrol. Risks for human trafficking exist not only while crossing the border but also after deportation.
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The Effect of Physico-Chemical Factors on the Stability and Transport of Clay ParticlesMusharova, Darya 2012 May 1900 (has links)
Clays which exist in formations in the vicinity of injection and disposal wells is a worldwide problem in the petroleum industry.
Clays can be categorized as two major groups: swelling clays, which include smectite group clays, and dispersing clays, which include the kaolinite groups of clays. Therefore, two basic damage mechanisms of clay minerals are swelling and dispersion. Both mechanisms cause pore plugging, and thus aggravate hydrocarbon ease of flow.
In this thesis, the effect of temperature, injected water chemical composition, pH, and flowrate of the injected fluid were tested experimentally. Clay mineralogy, chemistry, and composition of the exchangeable cations were also examined. The existing theoretical models of evaluation of forces between clay particles and the rock matrix were used to quantify the interactions.
Coreflood experiments were conducted to determine the effect of parameters such as variation of temperature, flowrate, pH, presence of various salts in working solution and their concentration.
The results obtained from experimental and theoretical work show that clay minerals in sandstone formation are subject to fines migration and can cause a detrimental impact on the reservoir permeability. Every aforementioned factor has its influence on clays behavior and therefore, a degree of fines migration. The work accomplished summarizes and concludes what parameters sensitize clays migration. Moreover, recommendations for formation damage due to fines migration are given. The scope of work presented can be useful for petroleum engineers as well as geologists and clay mineralogists.
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Migration Trends And Policies In Post-soviet RussiaUnsal, Duygu 01 September 2008 (has links) (PDF)
This thesis seeks to examine the internal and external migration trends in the Russian Federation. The thesis also examines the internal migration trends in the Soviet Union as well as Soviet emigration and migration policies. The thesis focuses mainly on the migration policy of the Russian Federation. The main argument of the thesis is that although ethnic dynamics, armed conflicts and nationalist clashes play important roles in Russia&rsquo / s migration trends, the main force of Russia&rsquo / s internal and external migration trends are economic.
The thesis has four main chapters. After the introduction the first chapter examines migration in the Soviet Union. The second chapter explores migration policy of Russia. The third chapter deals with internal migration in the Russian Federation. The last main chapter discusses external migration in the Russian Federation.
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Numerical modeling of gas migration into and through faulted sand reservoirs in Pabst Field (Main Pass East Block 259), northern Gulf of MexicoLi, Yuqian 16 August 2006 (has links)
The further exploration and development of Pabst Gas Field with faulted sand reservoirs require an understanding of the properties and roles of faults, particularly Low Throw near Vertical Faults (LTNVFs), in gas migration and accumulation at a reservoir scale. This study presents numerical modeling of gas migration and accumulation processes in Pabst Field. Based on studies of the reservoirs, structure, faults, and fluid properties of the field, reservoir scale modeling was performed to determine the gas supply style and the fault properties by means of hundreds of iterations in which the fault properties and gas supply pattern were modified to match the gas distribution obtained from modeling with the gas distribution inferred from seismic data constrained by well data and production data. This study finds that in the main three sand reservoirs of Pabst Field the overlying younger sands cut down into the underlying older sands, so that partial connections between the three sands allow gas communication among the sands. Meanwhile, three fault families break up the three sands into numerous compartments. A primary fault and large synthetic and antithetic faults act as gas migration pathways: the synthetic and antithetic faults are inlets for gas flow and the primary fault is an outlet, and LTNVFs act as barriers to gas flow. Modeling requires fault properties in the field to change while the field is formed. The porosity and permeability of the faults in Pabst Field are 10% and 0.1 md, respectively, during gas charging of the sand reservoirs. But when there is no gas charging and large gas columns are maintained, the porosity and permeability of the faults decrease to 6% and 0.001 md, respectively. Pabst Field probably has an impulse gas charge history. Fault opening and closing, gas charge and recharge, and replacement of gas by formation water may occur. A combination of stratigraphy, structure, overpressure and gas charge rate control gas migration style, gas charge history, and gas distribution in the field. The significance of the study is that this improved numerical approach for modeling gas migration into and through specifically faulted sand reservoirs fills the gap between basin modeling and production modeling.
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