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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Specific motifs responsible for protein-protein interaction between cannabinoid CB1 and dopamine D2 receptors

Zhang, Yun 07 November 2006 (has links)
Studying protein-protein interactions has been vital for understanding how proteins function within the cell, how biological processes are strictly regulated by these interactions, and what molecular mechanisms underlie cellular functions and diseases. Recent biochemical and biophysical studies have provided evidence supporting that G protein-coupled receptors (GPCRs) can and do interact with one another to form dimers or larger oligomeric complexes, which may determine the structure and function of GPCRs, including receptor trafficking, scaffolding and signaling. This may help to understand the physiological roles of GPCRs and mechanisms underlying certain disease pathologies and to provide an alternative approach for drug intervention.<p>Cannabinoid CB1 and dopamine D2 receptors are the most common GPCRs in the brain and exert a mutual regulation in brain functions involved in learning, memory and drug addiction. There is structural and functional evidence supporting the idea that CB1 and D2 receptors physically interact with each other in hippocampal and striatal neurons to modulate their functions. Direct evidence supporting a physical interaction between the CB1 and D2 receptors was obtained from cultured HEK293 cells stably coexpressed with both receptors.<p> This research project was designed to critically test the hypothesis that a specific protein sequence (i.e. motif) in the D2 receptor is responsible for in vitro protein-protein interactions between the CB1 and D2 receptors. To reach this goal, fusion proteins containing various domains and motifs of the CB1 and D2 receptors were prepared and then used first to determine the domains of the CB1 and D2 receptors responsible for in vitro protein-protein interactions between CB1 and D2 receptors, and then to identify the specific motifs in the D2 receptor responsible for in vitro CB1 coupling with the D2 receptors. The major method used in this study is in vitro pull-down assay, which uses a purified and tagged bait protein to generate a specific affinity support that is able to bind and purify a prey protein from a lysate sample. The present study provides the first evidence that CB1 intracellular C-terminal (CB1-CT) and D2 intracellular loop 3 (D2-IL3) can directly interact with each other, and that the specific motifs D2-IL3(Ⅳ1) and D2-IL3(Ⅳ3) in the D2 receptor are likely responsible for their in vitro coupling with the CB1 receptors. <p>The results of the present study are invaluable for future research exploring in vivo protein-protein interaction between the CB1 and D2 receptors in the rat striatum by co-immunoprecipitation. Specifically, future studies will determine whether the identified specific motifs D2-IL3(Ⅳ1) and D2-IL3(Ⅳ3) in the D2 receptor are indeed critical for their in vivo coupling with the CB1 receptors.
32

Study of dynamic effects in microparticle adhesion using Atomic force microscopy

Kaushik, Anshul 17 February 2005 (has links)
The adhesion and removal of particles from surfaces is a contemporary problem in many industrial applications like Semiconductor manufacturing, Bioaerosol removal, Pharmaceuticals, Adhesives and Petroleum industry. The complexity of the problem is due to the variety of factors like roughness, temperature, humidity, fluid medium etc. that affect pull-off of particles from surfaces. In particle removal from surfaces using fluid motion, the dynamic effects of particle separation will play an important role. Thus it is essential to study the dynamic effects of particle removal. Velocity of pull-off and force duration effects are two important dynamic factors that might affect pull-off. Particle adhesion studies can be made using the Atomic Force Microscope (AFM). The velocity of pull-off and force duration can be varied while making the AFM measurements. The objective of the current work is to obtain the dependence of pull-off force on pull-off velocity. Experiments were conducted using AFM and the data obtained from the experiments is processed to obtain plots for pull-off force vs. particle size and pull-off force vs. pull-off velocity. The pull-off force is compared with the predictions of previous contact adhesion theories. A velocity effect on pull-off force is observed from the experiments conducted.
33

Diversifiering inom jordbruket : En studie om de bakomliggande motiven att diversifiera

Löfling, Sarah January 2014 (has links)
No description available.
34

Análises in vivo e in vitro de interações intermoleculares da Beta-1,3- glicanosiltransferase 1 de Paracoccidioides brasiliensis / In vivo and in vitro analysis of Paracoccidioides brasiliensis Beta-1,3-glucanosyltransferase 1 intermolecular interactions

BAILÃO, Elisa Flávia Luiz Cardoso 28 January 2010 (has links)
Made available in DSpace on 2014-07-29T15:16:35Z (GMT). No. of bitstreams: 1 Dissertacao FINAL_EF_corrigida_BC-UFG.pdf: 1485117 bytes, checksum: ecdc9729cc08da2832a6566c39052f65 (MD5) Previous issue date: 2010-01-28 / The cell wall of pathogenic microbes acts as an initial barrier that is in contact with hostile environments. Besides functioning as a mechanical barrier, it harbours an immunogenic macromolecules arsenal. One of the ways that proteins can be associated to the cell wall, it is through GPI anchor. The hydrophobic C-terminal end of the &#946;-1,3-glucanosyltransferase enzyme of the human pathogenic fungus Paracoccidioides brasiliensis is characteristic of GPI anchored proteins. The &#946;-1,3-glucan assembling and rearrangement are essential since this molecule acts as a scaffold to support cell wall proteins and polysaccharides. In the thermodimorphic fungus P. brasiliensis, &#946;-1,3-glucan is found predominantly in mycelium form and &#945;-1,3-glucan is predominant in the yeast form. In this work, it was screened possible protein-protein interactions performed by &#946;-1,3-glucanosyltransferase 1 of P. brasiliensis (PbGel1p). To obtain these results, a P. brasiliensis cDNA library was screened with PbGel1p using the Saccharomyces cerevisiae two hybrid system. In addition, pull-down assay was used as an in vitro complementary technique to isolate proteins that interact direct or indirectly with PbGel1p. It was screened 38 gene products using two hybrid system and it was identified 3 proteins using the pull-down assay associated with mass spectrometry. The PbGel1p role in the cell wall maintenance and remodeling was indicated through the analysis of screened interactions, like alpha-glucosides permease, acid phosphatase, GDSL lipase, septin, actin, tubulin, HSP90 and pyruvate kinase. Furthermore, nuclear localization of PbGel1p and its role in the locus-specific transcriptional silencing were suggested based on such interactions: Qde2 argonaute, transcription elongation factor spt6, others transcription factors and ATP-citrate synthase. Therefore, this study indicated, for the first time, that PbGel1p has multiple location and it participates either in roles classically described for glucanosyltransferases, as the cell wall remodeling, or in recently described functions for this family of proteins, as the locus-specific transcriptional silencing. / A parede celular de microrganismos patogênicos atua como uma barreira inicial no contato entre o parasito e o hospedeiro. Além de funcionar como uma barreira mecânica, ela abriga um arsenal de macromoléculas imunogênicas. Uma forma pela qual as proteínas estão associadas à parede celular é por meio de âncoras-GPI. A extremidade carboxila hidrofóbica da enzima &#946;-1,3-glicanosiltransferase do fungo patogênico humano Paracoccidioides brasiliensis é característica de proteínas GPI-ancoradas. A montagem e o rearranjo de &#946;-1,3- glicana são de fundamental importância porque esta molécula serve como um esqueleto sobre o qual outros polissacarídeos e proteínas da parede celular estão associados. No fungo termodimórfico P. brasiliensis, &#946;-1,3-glicana é encontrada prioritariamente em micélio, sendo &#945;-1,3-glicana predominante em levedura. Foram rastreadas neste trabalho possíveis interações proteína-proteína realizadas pela &#946;-1,3-glicanosiltransferase 1 de P. brasiliensis (PbGel1p). Para isso utilizou-se a técnica de duplo-híbrido em Saccharomyces cerevisiae, rastreando-se uma biblioteca de cDNA do fungo P. brasiliensis com a enzima estudada. Adicionalmente, foi utilizado, como técnica complementar, o ensaio de pull-down, que isolou in vitro proteínas que interagem direta ou indiretamente com a PbGel1p. Foi possível rastrear 38 produtos gênicos através do sistema de duplo híbrido e isolar três proteínas pelo ensaio de pull-down, identificadas por espectrometria de massas. O papel da PbGel1p na manutenção e no remodelamento da parede celular do fungo foi indicado através da análise das interações rastreadas, como permease de &#945;-glicosídeos, fosfatase ácida, lipase da família GDSL, septina, actina, tubulina, HSP90 e piruvato quinase. Além disso, foram sugeridos a localização da PbGel1p no núcleo das células do fungo e seu papel no silenciamento gênico mediado por alterações estruturais, por meio do rastreamento das seguintes proteínas ligantes a PbGel1p: argonauta Qde2, fator de alongamento transcricional spt6, outros fatores transcricionais e ATP-citrato sintase. Portanto, este estudo indicou, pela primeira vez, que PbGel1p tem localização múltipla e participa tanto de funções classicamente descritas para glicanosiltransferases, como o remodelamento da parede celular, quanto de funções recentemente descritas para essa família de proteínas, como o silenciamento transcricional sítio-específico.
35

Emigranterna från Sunnerbo härad : Emigrationen från Sunnerbo härads socknar under åren 1880-1889. / The emigrants from Sunnerbo district : The emigration from Sunnerbo district during the 1880s

Bergsjö, Ronja January 2021 (has links)
The purpose of this essay is to investigate the emigration from Sunnerbo district, whichis located in western Kronoberg county, during the 1880s. The goal is to find out whothe emigrants were and how and where they planned to emigrate. This is accomplishedby looking at the emigrants' gender, age, title or professional title as well as familyrelationship and country of destination. Information has been found in digital archives,relocation books have been read in the Digital Archive and population reports have beenread in the National Archives' digital research hall. From this material it can be deducedthat 7432 people emigrated in the 1880s, corresponded to 17.6% of Sunnerbo's averagepopulation and that 49% of the emigrants were women. The majority were in the agerange 20-29 years with a profession linked to agriculture. One third emigrated with theirfamilies and 85.8% emigrated to North America. The results of the empirical study arediscussed with previous research and theories related to migration. An analysis of themigration within Sunnerbo district will also be carried out to discuss differences betweenthe 23 parishes within the district. / Denna uppsats syfte är att undersöka emigrationen från Sunnerbo härad, som ligger ivästra Kronobergs län, under 1880-talet. Målet är att ta reda på vilka emigranterna varsamt hur och vart de planerade att emigrera. Detta görs genom att kartläggaemigranternas kön, ålder, titel eller yrkestitel samt familjeförhållande ochdestinationsland. Informationen har funnits i digitala arkiv. Utflyttningsböcker harhämtats ur Arkiv digital och folkmängdsredogörelser är lästa i Riksarkivets digitalaforskarsal. Från detta material kan det utläsas att 7432 människor emigrerade under1880-talet, motsvarade 17,6% av Sunnerbos genomsnittliga befolkning och att 49% avemigranterna var kvinnor. Majoriteten var i åldersintervallet 20-29 år med ett yrkekopplat till jordbruk. En tredjedel emigrerade ihop med sin familj och 85,8% emigreradetill Nordamerika. Resultaten av den empiriska undersökningen diskuteras med tidigareforskning och teorier kopplade till migration. En analys av migrationen inom Sunnerbohärad kommer även att genomföras för att diskutera skillnader mellan de 23 socknarnainom häradet.
36

Optimalizace zásob prostřednictvím KANBANu / The KANBAN Optimalization of Inventory

Ševčíková, Jitka January 2007 (has links)
This thesis deals with implementation of another supplier to the Kanban system in the company Lexmark International s.r.o. The first part of the thesis is concerned with a theoretical finding from literature concerning inventory, types of supplies, level of inventory, calculation of supplies and, in addition, the Kanban and JIT system. The operative part is dedicated to analyses of the current status of the company using of the Porter´s, SWOT and SLEPTE analyses and, more over, the process of supplies by the method of PUSH and PULL – Kanban system in the company. The following chapter compiles the project on optimalization and decreasing of inventory by implementation of the Kanban system by Asian suppliers whose inventory coveres a substantial part of the company´s value. The objective of this thesis is to find whether the implementation of Kanban reduces level of inventory and whether their costs can be reduced in comparison with the last years and last but not least whether the implementation can be useful.
37

Home is where the heart is : En studie i platsanknytning och dess påverkan på valet av framtida bostadsort

Byström, Oskar January 2016 (has links)
Uppsatsen har som syfte att undersöka studenter vid Uppsala universitets syn på sin hembygd, deras nuvarande bostadsort och deras inställningar till att flytta tillbaka till hembygden. Detta görs med hjälp av kvalitativa respondentundersökningar i form av semistrukturerade intervjuer med studenter vid Uppsala universitet. Totalt har sex studenter deltagit i intervjustudien. Resultatet visar att studenterna har liknande uppfattningar av sin hembygd trots att de kommer från vitt skilda platser i Sverige. Hembygden ses som liten vilket har både positiva och negativa attribut. De har även en enhetlig uppfattning av den nuvarande bostadsorten Uppsala vilken ses som en plats som passar väl in i deras nuvarande livssituation. Respondenterna har skapat nya sociala nätverk i Uppsala och säger sig trivas bra i staden. Detta påverkar deras inställningar till att flytta tillbaka till hembygden då det i nuläget anses vara en större förlust att återvända eftersom det kan medföra att det nya sociala nätverket som skapats i Uppsala skulle försvinna. Deras livssituation i dagsläget anses inte heller vara kompatibelt med livet i hembygden. I samtliga intervjuer framgår det att respondenterna för närvarande inte har några planer på att återvända till hembygden.
38

Processen från flyktingsskap till etablering i ett nytt samhälle

Shahho, Jasmin January 2016 (has links)
Syftet med denna studie är att med hjälp av kvalitativ metod få en förståelse till vilka strategier invandrare väljer att använda sig utav för att etablera sitt liv i ett nytt land. Frågeställningarna i denna studie är: Hur upplevs förändringsprocessen från flyktingskap till etablering i ett nytt samhälle? Vilka utmaningar upplever människor i dessa processer?
39

FLIGHT TEST INSTRUMENTATION OF THE PUSH-PULL EFFECT ON A CF-18 AIRCRAFT

Caballero, Rubén 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During high performance fighter aircraft manoeuvres, a fighter pilot may be exposed to a physiological phenomenon known as the “Push-Pull Effect” (reference (ref) [1]). This effect will alter the pilot’s homeostasis whereas blood flow to the brain will be increased during low negative normal acceleration (-Gz) and suddenly decreased during positive normal acceleration (+Gz). It has been hypothesized that this effect can lessen the Gtolerance of the human body thereby making the subject more susceptible to G induced Loss of Consciousness (G-LOC) (refs [2], [3] and [4]). G-LOC is not a desirable state for a pilot in a high performance aircraft such as a CF-18. To better understand and study the Push-Pull Effect on a fighter pilot, the Aerospace Engineering Test Establishment (AETE) and the Defence and Civil Institute of Environmental Medicine (DCIEM) produced an In-Flight Research (IFR) Program sponsored by the Canadian Forces (CF). The aim of this program was to measure the physiological response of relaxed test subjects, unprotected by a G-suit, when exposed to the Push-Pull manoeuvre in flight. This IFR would validate the centrifuge data and confirm that the Push-Pull Effect can occur in flight. This paper will present the instrumentation, design, telemetry system and installation methodology utilized to perform experimental physiological research on a high performance, ejection seat equipped fighter aircraft (CF-18). Also, preliminary results on the Push-Pull Effect, obtained through this IFR Program will be presented.
40

Push-pull’s factors influencing exchange student’s destination choice for study abroad : A case study of the students at JIBS

Vo, Mai-Thuy-Tien, Muntasira, Rafia, Jiang, Ming-ming January 2009 (has links)
<p>‘Internationalisation of higher education’ is considered a significant issue in many countries.One effective way to achieve internationalisation is by having an exchange study program. Thisis something which has been promoted by universities all around the globe. It has been foundthat the experience of studying abroad is beneficial to the students. There has been a trend ofincreasing number of students going to study abroad. In Sweden, Jönköping InternationalBusiness School (JIBS) is one of the most internationalised business schools that promoteexchange studies extensively. To promote study abroad it is important to know what motivatesand influences the students to go on exchange. There has been previous research oninternationalisation and push-pull factors of student mobility which acted as a guideline for thisthesis. Thus it was appealing to study the reasons behind the phenomenon of students goingabroad for exchange studies.The purpose of this paper is to explore the push-pull factors influencing student’s destinationchoice for exchange study abroad. JIBS is the institution where the case study was conducted.The empirical data have been gathered by using a qualitative approach combining face-to-faceinterviews and focus groups with international exchange students and Swedish students. Toanalyse the findings, theories relating to marketing communications in service and productattribution were used.The results derived from the empirical findings show the push-pull factors which motivatestudents to go on exchange. The initial push factor is the promotion and encouragement tostudents for studying abroad by the university. Exchange studies helps to enhance students’personal development with intercultural communication, practicing language skills andtravelling. These skills and experiences add value to their CV.On the other hand the pull factors which the students take into consideration for deciding ontheir host countries and institutions are geographic location, weather, culture, and the economicand social position of the country. Living cost and the education system which includeslanguage used, courses offered, perceived image, communication and cooperation andrecommendations are factors influencing the choices of a student’s decision on the destinationfor studying abroad. The authors in this thesis summarised their findings in a model of pushpullfactors which is specialised only for exchange students. The process of considering thesefactors leads to the outcome of choosing the destination for studying abroad. The authorsbelieve the results of this study can be applied on other universities for further research andmay be appropriate for its own case to focus on areas where it needs to improve.ii</p>

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