357 research outputs found
Characterization of exosomes from glioma cells under hypoxia
Exosomes are cell-secreted nanosized (30-200 nm) membrane vesicles that contain cytosol proteins and nucleic acids (mRNA, miRNA and mDNA). They have been characterized to be released by most cell types and thus, represent an important part of cell-cell communication. Especially they might play an important role in cell adaptation processes to stress conditions such as hypoxia or oxidative stress. The main difficulty in studying exosomes is however their purification and characterization process which is still a major challenge in the field of exosome research. In this study, we set up the method for isolation of exosomes with differential centrifugation and two characterization techniques nanoparticle tracking analysis (NTA) and bicinchoninic acid assay (BCA). With the latter techniques we studied whether glioma cells exposed to stress conditions produce more exosomes as communication messengers compared to standard environment. The study so far did not answer this question, our data nevertheless show the initial evidence that exosomes reflect the inner metabolic status of cells.Characterization of exosomes All multicellular living systems rely on cellular communication in order to form functional organisms. This communication is dependent on physical contact between cell membranes, free diffusion of small cell-secreted soluble molecules and cell-secreted lipid vesicles. Among those are also exosomes which have been found to be released by most cells types. They vary in size between 30 and 200 nm and contain proteins and nucleic acids. Because exosomes are very small in size and their density can overlap with other particles in the samples, their isolation and purification is still a major challenge in the field of exosome research. Generally they are isolated with differential centrifugation which consists of a step-by-step removal of bigger contaminating particles until the final ultra-centrifugation to pellet exosomes. To characterize exosomes and check whether they are pure one has to determine the presence of exosomal markers and contaminants, the size-distribution of particles in the sample and the density gradient with sucrose. I set up the methods for exosome isolation, size distribution and protein measurements. These measurements showed that exosomes were present in the sample but were not highly purified. Further analysis with sucrose gradient centrifugation, electron microscopy and specific protein identification will be performed in the future. Release of exosomes from glioma cells under hypoxia and oxidative stress In this study I investigated whether glioma cells release more exosomes under stress compared to standard environment. Glioma is a type of cancer that arises from glial cells in the brain. Two glioma cell lines, U87-MG (high-grade glioma) and H4 (low-grade glioma), were exposed to mimicked hypoxia (i.e. low oxygen) and oxidative stress (i.e. high presence of reactive oxygen species). The qualitative analysis of the exosomal proteasome (i.e. protein content) showed the initial evidence that exosomes reflect the inner metabolic status of cells. Exosomes isolated from hypoxia-treated cells were enriched in ribosomal proteins, which represent a higher metabolical activity under stress. Furthermore, the exosomes were depleted in proteins involved in the modulation of extracellular matrix (ECM) which might indicate a differential need for those proteins due to morphological changes that cells experience under stress. Overall the study did not provide definite and clear answers to the influence of stress on exosomes release and composition and more experiments are required before drawing final conclusions. Supervisor: Georg Kuhn Master’s Degree Project in Neurobiology, 45 ECTS, 2015 Research group Georg Kuhn, Sahlgrenska academy, Göteborg
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The Grand Challenge of Carbon Sequestration
This paper won a third place writing flag award in the collaborative category. Clayton Lawrence, Thomas Nguyen, Mitchell Tomazin, and Norberto Martinez, writing for Brandi DeMont 's ASE 333T class, " Engineering Communication ".DeMont, BrandiUndergraduate Studie
Task Specificity and Functional Outcome: What is best for Post-Stroke Rehabilitation?
Stroke is a debilitating insult to the brain occurring from a blockage in blood supply (ischemic), or a bleed (hemorrhagic) in one hemisphere of the brain. Worldwide, approximately 10 million people are left with moderate to severe disability due to stroke; the most common deficit is upper extremity impairment. Current stroke rehabilitation strategies utilize task specific training of a skill, meaning one practices the specific skill they want to regain. However, it is possible that there are more generalized types of therapy that can be as effective in rehabilitating debilitated skills. The current study utilizes several skilled reaching tasks in mice which show striking parallels to human dexterous movements in order to observe the effects of task-specific versus generalized upper extremity rehabilitation post-stroke. Our findings through statistical and kinematic analysis have implications that task-specific rehabilitative strategies may promote more true recovery than compensation due to the lesser degree of abnormalities in movement post-training as compared to generalized therapy and control groups. Findings also support the validity of a skilled reaching task used in the rodent model; however, further studies and analysis are necessary
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The role of the Western engineer in the emerging Asian multinational corporation
textIn recent years there has been a growing trend of Western companies outsourcing many engineering jobs to Taiwan, India, and China. While companies have been outsourcing and moving manufacturing jobs for decades, there is a recent acceleration of sending “high tech” engineering jobs overseas. While the job loss in the Western world is alarming to Western engineers, there is another trend that is keeping jobs in the West that deserves some consideration. Asian multinational corporations are acquiring engineering operations in the United States and Europe. Since there is seemingly abundant talent available in their home countries, what motivates these Asian multinational corporations to invest in Western engineering operations? Is this investment a long term viable employment option for Western engineers? This paper will address these two critical questions.Engineering Managemen
RELATIONSHIP BETWEEN VERTICAL JUMPS AND STARTING ACCELERATION IN SPRINT
The purpose of this study was to relate standardized vertical jumps with acceleration phase in sprint. Since vertical jumps employ typical kinetic chains and provide insight into basic movement strategies of the athlete, they may provide additional information about the nature of sprint acceleration phase
Lawyer as business owner
Magistrsko delo obravnava znanja, pretežno poslovna, ki so ključna pri vodenju podjetja. Ko v vlogi poslovodje nastopa pravnik, je tako potrebno, da poleg pravnih razpolaga tudi s poslovnimi znanji. V jedru dela so obravnavani trije poslovni modeli oz. poslovna orodja, in sicer Canvas, SWOT analiza in pa Porterjevih pet silnic. Poslovno orodje Canvas zajame celotno poslovanje podjetja, od dobaviteljske mreže, ustvarjanja produkta, prodaje, do denarnih tokov, zato je uporabno predvsem takrat, ko želimo v celoti (z vseh zornih kotov) preveriti poslovno stanje podjetja. SWOT analiza, pri kateri se osredotočamo na prednosti in pomanjkljivosti poslovnega načrta, je uporabna širše, ne le pri analizi poslovanja podjetja. Lahko jo uporabimo tudi zunaj okvirov poslovodenja. Porterjevih pet silnic je poslovni model, s katerim lahko analiziramo konkurenčnost okolja in podjetja. V zaključku dela so podana še dodatna znanja, ki so ključna za vodenje podjetja. Gre prvi vrsti za znanja, ki se uvrščajo pod mehke oz. socialne veščine.
V drugi polovici dela je obravnavana povezava med študijskim načrtom pravne fakultete in poslovnimi znanji. Predlagani so tudi ukrepi za izboljšave. V zaključku dela je podan odgovor na raziskovalne hipoteze in ponovno poudarjena pomembnost poslovnih znanj za kariero pravnika, ki se želi podati v poslovodenje.The master\u27s thesis deals with knowledge, mainly related to business, which is essential in managing a company. When a lawyer acts as a business leader / manager, it is so necessary that in addition to legal, he also possesses business skills. At the core of the paper, three business models are considered. Business tools, namely Canvas, SWOT analysis and the Porter\u27s five forces. The business tool Canvas captures the whole business of the company, from the supplier network, the creation of products, sales, to cash flows, so it is useful especially when we want to verify the business situation as a whole (from all angles). The SWOT analysis, focusing on the advantages in the shortcomings of the business plan, is useful wider, not only in the analysis of the company\u27s operations. We can also use it outside of our leadership. Porter\u27s five forces is a business model that can analyze the competitiveness of the environment and businesses. At the end of the paper, additional knowledge is listed, which is crucial for the management of the company - primarily social skills.
In the second half of the paper, the link between the study plan of the Faculty of Law and business knowledge is discussed. Improvements are also proposed. The conclusion of the work is the answer to the research hypotheses and the re-emphasized importance of business knowledge for the career of a lawyer who wants to become a business leader
The role of job satisfaction in explaining relationship between social support and job performance
Cilj ovog istraživanja bio je ispitati povezanost socijalne podrške, kao jedne od socijalnih karakteristika posla koja prvotno nije uključena u Model karakteristike posla Hackmana i Oldhama (1976), sa zadovoljstvom poslom, uspjehom u radnim zadacima i odgovornim organizacijskim ponašanjem. Cilj je također bio ispitati posreduje li zadovoljstvo poslom odnosu socijalne podrške i uspjeha u radnim zadacima te odnosu socijalne podrške i odgovornog organizacijskog ponašanja. Ukupno je 190 odraslih zaposlenih ispitanika ispunjavalo Upitnik socijalne podrške (Morgeson i Humphrey, 2006), Indeks zadovoljstva poslom (Brayfield i Rothe, 1951), Upitnik odgovornog organizacijskog ponašanja (Fox i sur., 2012) i Upitnik uspjeha u radnim zadacima (Williams i Anderson, 1991). Rezultati su pokazali da je socijalna podrška značajno povezana sa zadovoljstvom poslom, uspjehom u radnim zadacima i odgovornim organizacijskim ponašanjem. Medijacijskom analizom utvrđeno je da zadovoljstvo poslom posreduje u povezanosti socijalne podrške i uspjeha u radnim zadacima. Ovakav medijacijski odnos nije se mogao testirati kada je kriterij bio odgovorno organizacijsko ponašanje zbog nepostojanja povezanosti zadovoljstva poslom i odgovornog organizacijskog ponašanja. Rezultati provedenog istraživanja imaju praktične implikacije za psihologe u ljudskim resursima, menadžere i voditelje timova. Povećanjem socijalne podrške među zaposlenicima i nadređenima povećava se uspješnost u izvođenju radnih zadataka, a ta veza potpuno je posredovana zadovoljstvom poslom.The aim of this study was to examine the relationship between social support, as one of the social characteristics of the job that was originally not included in the Job characteristics model (Hackman and Oldham, 1976), with job satisfaction, task performance and organizational citizenship behavior. The aim was also to examine whether job satisfaction mediates the relationship of social support and task performance and relative social support and organizational citizenship behavior. A total of 190 respondents, all of them employed adults, filled out the Social Support Questionnaire (Morgeson and Humphrey, 2006), Index od Job Satisfaction (Brayfield and Rothe, 1951), Organizational Citizenship Behavior Checklist (Fox et al., 2012) and the Task Performance Questionnaire (Williams Anderson, 1991). Results showed that social support is associated with job satisfaction, task performance and organizational citizenship behavior. Mediation analysis showed that job satisfaction mediates the relationship between social support and task performance. Due to lack of a relationship between job satisfaction and organizational citizenship behavior, this kind of mediation relationship could not be tested with responsible organizational citizenship behavior as a criterion. The research results have practical implications for psychologists in human resources, managers and team leaders. Increasing social support among employees and supervisors increased success in performing their tasks, and this connection is completely mediated by job satisfaction
Inclusão social e políticas públicas : distanciamento entre teoria e prática do programa de regionalização do turismo - roteiros do Brasil. estudo de caso : Aracati e Jijoca de Jericoacoara (CE)
Dissertação (mestrado)—Universidade de Brasília, Centro de Excelência em Turismo, Mestrado Profissional em Turismo, 2016.A presente dissertação tem como objetivo analisar os impactos sociais sobre a qualidade das políticas públicas no campo do turismo, tendo como indicador a inclusão social e como objeto de estudo o Programa de Regionalização do Turismo – Roteiros do Brasil do Ministério do Turismo, o qual foi implementado em 2004 e requer uma análise crítica após 10 anos de execução. O método utilizado na investigação foi o materialismo histórico dialético, pois desvelar a essência do fenômeno estudado e não ficar na descrição restrita do mesmo, requer estabelecer as contradições entre teoria/prática, objetividade/subjetividade do processo histórico ocorrido. Para melhor desvelar a problematização proposta sobre quais foram, no processo histórico concreto dos territórios, os impactos sociais do PRT e se sua ação indutora contribuiu para a inclusão social ou limitou-se a uma política pública restrita aos interesses de mercado, adotou-se uma abordagem qualitativa, consistindo da construção do referencial teórico sobre as teorias sociais relacionadas geradoras de categorias operatórias como: desenvolvimento, inclusão social, cidadania, turismo, políticas públicas de turismo, regionalização, roteirização. No traçado metodológico utilizou-se da análise documental (CELLARD, 2012) sobre o processo de regionalização do turismo, como ação indutora do Ministério do Turismo, entre os anos de 2004-2014, somado ao trabalho de campo com entrevistas e observação livre com o estudo de caso múltiplo de 02 destinos indutores - Aracati e Jijoca de Jericoacoara, localizados no Estado do Ceará, permitindo, assim, a construção de evidências referentes ao processo do tipo de desenvolvimento e dos impactos sociais da política pública expressa pelo PRT. O Índice de Desenvolvimento Humano Municipal e o Índice FIRJAN de Desenvolvimento Municipal serviram como indicadores sociais somados ao Índice de Competitividade do Turismo Nacional – 65 Destinos Indutores do Desenvolvimento Turístico Regional (FGV,MTUR,SEBRAE). As evidências possíveis pelo método do MHD permitiu observar o distanciamento existente entre teoria e prática do PRT, posto que a opção ideológica adotada pelo MTur em relação à concepção do turismo e de desenvolvimento pelo turismo delineia-se em uma ação fragmentada, na qual tanto a comunidade, quanto as instâncias de governança são pautadas pela concepção do mercado, o que impossibilitou o impacto social emancipador da comunidade local pelo PRT, embora em seu plano abstrato formal a teoria se apresente como uma possibilidade.This thesis aims to analyze the social impact on the quality of public policies in the field of tourism, with the indicator of social inclusion and as an object of study the Regionalization Program of Tourism - Routes of Brazil's Ministry of Tourism, which was implemented in 2004 and requires a critical analysis after 10 years of implementation. The method used in the research was the dialectical historical materialism, for revealing the essence of the phenomenon studied and not to be restricted in the description of it requires to establish the contradictions between theory / practice, objectivity / subjectivity of the historical process occurred. To better reveal the problematic proposal on which were, in this historical process of the territories, the social impacts of the PRT and its catalytic action has contributed to social inclusion or merely a public policy restricted to market interests, it adopted one qualitative approach, consisting on deconstruction the theoretical framework on related social generator theories of operative categories as: development, social inclusion, citizenship, tourism, public policies for tourism, regionalization, routing. Methodological route was used documentary analysis (Cellard, 2012) on the tourism regionalization process, such as catalytic action of the Ministry of Tourism, between the years 2004-2014, added to the field work with interviews and free observation with multiple case study of 02 destinations inducers - Aracati and Jijoca Jericoacoara, in the State of Ceará, thus allowing the construction of evidence relating to the type of development process and social impacts of public policy expressed by the PRT. The Municipal Human Development Index and the Municipal Development FIRJAN Index served as social indicators added to Competitiveness of National Tourism - 65 destinations inducers of Regional Tourism Development (FGV, MTUR, SEBRAE). Possible evidence for MHD method allowed to observe the existing gap between theory and practice of PRT, since the ideological option adopted by MTur in relation to the design of tourism and development at tourism delineating in a fragmented action, in which both the community, as governance bodies are guided by the concept of the market, which prevented the emancipatory social impact of the local community by PRT, although in its formal abstract plan theory is presented as a possibility
Govor vasi Topole
This article presents the subdialect of the village of Topole, located on the road from Mengeš to Brnik. It has the phonological and morphological characteristics of a typical Upper Carniolan dialect of Slovenian. According to Ramovš’ classification, the Topole subdialect belongs to central Upper Carniolan, spoken in the Ljubljana-Kamnik-Kranj triangle. In addition to a phonological description, the article also presents phrasemes in very widespread use locally, followed by a Topole dialect–standard Slovenian glossary.V prispevku je predstavljen govor vasi Topole, ki leži ob cesti Mengeš–Brnik. V njem se odražajo glasoslovne in oblikoslovne značilnosti tipičnega gorenjskega narečja. Po Ramovševi klasifikaciji spada topolska govorica v osrednji gorenjski govor, ki se govori v trikotniku Ljubljana–Kamnik–Kranj. Poleg glasovnega opisa so v razpravi predstavljeni tudi lokalno zelo razširjeni frazemi, temu pa sledi še topolsko-knjižnoslovenski slovarček
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