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A STUDY OF THE EFFECTS OF REVIEW, SOCIAL, AND ADOPTER CHARACTERISTICS IN MOBILE APP ADOPTIONLiu, Fengkun 20 October 2014 (has links)
No description available.
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Medierat Brus: En studie i information overload & sociala medierGrimberg, Christian, Ljungberg, Caroline January 2013 (has links)
Det har länge dividerats om hur den teknologiska utvecklingen påverkar oss. Marshall McLuhan och Alvin Toffler ifrågasatte vårt beteende och berättade om hur teknikens utveckling kommer att påverka oss redan på 1960-talet. Det har också myntats uttryck som information overload och infobesity som uttrycker den stress människor upplever när de inte längre kan bearbeta den information de konstant tar del av. Sociala medier är en stor bidragande faktor till det rådande tillståndet av information overload. Det råder inte heller några tvivel om att vår användning av sociala medier mer eller mindre påverkar våra medvetna beslut och vår kommunikation.Information overload är inget nytt begrepp, och i dagens informationssamhälle är det inte bara massmedia som står för den informationsspridning som sköljer över befolkningen utan de är själva delaktiga i att skapa den enorma mängd information och kommunikation de tar del av varje dag. Medierad kommunikation är under ständig utveckling och tar en stor plats i vårt vardagsliv. Det är inte enbart den klassiska masskommunikationen som fångar användarnas uppmärksamhet utan det är möjligheten att själva vara med och bidra till kommunikation och information som är intressant för användaren.Det är av vår uppfattning att de moderna kommunikationsverktygen påverkar vårt varande, både i den digitala och den verkliga världen, och det är denna påverkan som är i fokus för denna studie. / Today’s interactive media invites users to take part in a massive exchange of information and the idea and desire to filter information has always been in question. This thesis will discuss the problems with information overload and the effects it has on users of social media. With critical design as a point of view we aim to point out some of these effects in an attempt to create a debate within the interaction design community. The first chapter will discuss the theories underlying mediated communication, information overload, user centered design and critical design. The following chapters will discuss methodology and implementation of these methods. Bodystorming and user studies will function as our main methods to map out the behavioural changes that come from information overload. The result of our user studies indicates that the communication often becomes impersonal and that the activity itself becomes more important than the content of the message. Our final results will not present a solution to the problem area but will give an example on how to focus design work to avoid creating unpleasant user experiences of social and interactive media.
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Digitalt skrivande: En möjlighet eller ett hinder i dagens klassrum? / Digital writing: An opportunity or a drawback in today´s classroom?Jevring, Alexandra January 2020 (has links)
Den ökande digitaliseringen i matematikklassrum på gymnasiet ställer allt högre krav på eleverna. Enligt de senaste bestämmelserna ska nationella prov inom några få år genomföras digitalt. Detta innebär att eleverna kommer att behöva skriva in sina lösningar på datorer. Detta arbete är uppdelat i två delar. Syftet med första delen är att undersöka om det förekommer en synlig påverkan på elevernas prestation i matematik på gymnasiet beroende på om de löser problem på papper eller på dator. Denna del skapas med hjälp av tidigare forskning i detta område och går ut på att eleverna genomför två prov där de använder sig av antingen papper eller datorer för att lösa problem. Syftet med andra delen är att ta fram rekommendationer som bör underlätta för lärare att introducera eleverna till att skriva matematik på datorer. För denna del i arbetet genomförs intervjuer med lärare och elever på en gymnasieskola. Resultat från prov, i första delen av arbetet, visar att eleverna presterar sämre i grupper där de inte är vana med att arbeta på datorer. Svar från intervjun i andra delen visar att det finns många aspekter som läraren behöver tänka på när eleverna ska börja arbeta med datorer i matematikundervisningen. Utifrån intervjuer formas rekommendationer för lärare som redovisas i detta arbete. Sammanfattningsvis visar detta arbete att eleverna behöver mer övning för att kunna prestera lika bra på dator som de skulle göra om de löser problem på papper. Eftersom studien genomfördes på en gymnasieskola behövs det mer forskning som undersöker om samma trend kan ses i andra gymnasieskolor. / The increasing digitalisation in mathematics classrooms places ever higher demands on students. According to the latest regulations, national tests must be carried out digitally in a few years. This means that students will need to enter their solutions on computers. This work is divided into two parts. The purpose of the first part is to investigate whether there is a visible impact on students' performance in mathematics in high school, depending on whether they solve problems on paper or on a computer. This part is created with the help of a literature study and involves the students completing two tests where they use either paper or computers to solve problems. The purpose of the second part is to produce recommendations that should make it easier for teachers to introduce students to writing mathematics on computers. For this part of the work, the interviews were conducted with teachers and students at a high school. The results from tests, in the first part of the work show that the students perform worse in groups where they are not used to working on computers. Answers from the interview in the second part show that there are many aspects that the teacher needs to keep in mind when students start working with computers in mathematics teaching. Based on interviews, recommendations are formed for teachers that are presented in this work. In summary, this work shows that students need more practice to be able to perform as well on a computer as they would if they solved problems on paper. Since the study was conducted at one high school, more research is needed that examines whether the same trend can be seen in other high schools.
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Consumer as Inforagers: Ecological Information Foraging under Information Overload Paradigm - An Integrative Perspective between Darwinism and Non-DarwinismKim, Wooyang January 2014 (has links)
The main purpose of this dissertation is to assess ontological issues of information acquisition, focusing on information overload from an integrative perspective of two theoretical foundations, which links two perspectives of consumer behavior in information acquisition: foraging theory in behavioral ecology and information processing theory in marketing. Applying to the integrative investigation, the current research primarily emphasizes the infusion of ecological rationality (i.e., Darwinian Theory) into normative rationality (i.e., Newtonian Theory), but it is not alternative but complementary to each other. Ecological rationality, which is rooted in Darwinism, emphasizes that human behavior has developed through adaptation and natural selection as the human minds interact with environments. The current study consists of five chapters: the philosophical foundation of the rationalities, exploratory study, proposed hypotheses, empirical tests, and general discussion. A summary of the contents of each chapter is: The first chapter aims to provide an integrative framework of consumer information acquisition in order to explore ontological issues in information overload paradigm, attempting to synthesize different approaches in marketing and behavioral ecology. To explore, the current study emphasizes an integrative perspective between two theories for information acquisition (foraging and information processing), which are based on different philosophical foundations of the rationality (ecological and normative). Along with the process of the information acquisition, this study provides relevant consequences (decision-related responses and decision-related alternatives) after the information acquisition process and influential factors in temporal and psychological dimensions (time and motivation). Then, the conceptual study provides conclusion and the current research scope. The second chapter aims to examine the efficacy of the current study's theoretical integration in the process of consumer information foraging so as to approach an ontological issue in information overload paradigm: more information is better vs. less information is better (i.e., information processing theory and foraging theory under an information overload paradigm). Therefore, this study explores and examines what can be appropriate information structures to describe the ontological issue in the process of consumer information foraging. To formulate the adequate information structure, this study attempts to utilize an integrative perspective between marketing and behavioral ecology. This study examines consumers' online activities sequentially from a broad to detail approach, based on the categories of goods and services. The result, by and large, suggests a necessity of an integrative perspective to view a holistic information structure, including quantity, quality, and environment components. These structural components interactively communicate with minds when shaping the process of the consumer information foraging, which are likely to involve in the degree of information overload. Moreover, results demonstrate rather higher variation of strategic information foraging but emphasize some important communality in the initial stage of information foraging, such as the role of search engine and interpersonal communication. In addition, categories of goods and services affect shaping the pattern of strategic information foraging. Then, the conclusion of the study provides. The third chapter aims to propose a hypothetical model, based on the theoretical backgrounds in Chapter 1 and the findings of the exploratory study in Chapter 2. In addition, the pilot study was conducted to provide a concrete framework of the empirical study by checking the manipulation of holistic information structures. The manipulation of the structures includes the total quantity of information, the quality of information, and environmental information. Those structures measured on several resultant consequences, using the patch concepts (within-patch and between-patch). Controversially, in general, consumers tend to prefer more information rather than less information only when arranged information provides; otherwise, this preference attenuates. This controversial result also has conflicting variations, depending on the types of patches. Overall, the comparison in the within-patch and between-patch through displaying heterogeneous information structures suggests that holistic information structures are a more important factor than the mere quantity or quality of information. The fourth chapter empirically tests the theory-based hypothetical frameworks to assess the ontological issues in information overload paradigm using the integrative perspective of the two information acquisition theories. The findings of the empirical study suggest that the real-world information overload is not simply determined by a single dominant factor (e.g., quantity), but by the interplay of intricately intertwined factors. The factors are the following: information structures (three unarranged and four arranged information structures, including quantity, quality and environment), item categories (durables, nondurables and services), and time constraints (time pressure vs. no time pressure). The interwoven complexity implies that paradigmatic change of perspectives in relation with information overload though integrating two important conceptual factors between domain-specific dependency and universality. Moreover, the information overload begins with the browsing stage of acquiring the necessary information, not with the searching stage, suggesting the view of browsing-searching continuum that underscores the important role of the patch concept. As a whole, the conclusive findings suggest an integrative perspective between Darwinism and Non-Darwinism as a prerequisite of providing a better comprehension of the issues of the information overload paradigm. The fifth chapter is the section of general discussion including major findings, theoretical, methodological and empirical implications, limitations, and conclusive statement. / Business Administration/Marketing
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Energy-Efficient, Utility Accrual Real-Time SchedulingWu, Haisang 29 August 2005 (has links)
In this dissertation, we consider timeliness and energy optimization in battery-powered, mobile embedded real-time systems. We focus on real-time systems that operate in environments with dynamically uncertain properties, including context-dependent activity execution times and arbitrary activity arrival patterns. We consider an application model where activities are subject to time/utility function (or TUF) time constraints, mutual exclusion constraints on concurrent sharing of non-CPU resources, timeliness requirements including assurances on individual activity timeliness behavior, and system-level energy consumption requirements including a non-exhaustable energy budget.
To account for uncertainties in activity properties in dynamic systems, we stochastically describe activity execution demands, and describe activity arrival behaviors using the unimodal arbitrary arrival model, which allows unbounded arrival frequencies. We consider the scheduling optimality criteria of: (1) probabilistically satisfying lower bounds on individual activities' maximal timeliness utilities, and (2) maximizing system-level energy efficiency, while ensuring that the system's energy consumption never exhausts the energy budget and resource mutual exclusion constraints are satisfied.
For this multi-criteria scheduling problem, we present a DVS (dynamic voltage scaling)-based, real-time scheduling algorithm called the Energy-Bounded Utility Accrual Algorithm (or EBUA). Since the scheduling problem is NP-hard, EBUA heuristically (and dynamically) allocates CPU cycles to activities, computes activity schedules, and scales CPU voltage and frequency with a polynomial-time cost. If activities' cumulative execution demands exceed the available CPU time or may exhaust the system's energy budget, the algorithm defers and rejects jobs in a controlled fashion, minimizing system-level energy consumption and maximizing total accrued utility.
We analytically establish several properties of EBUA. We prove that the algorithm never exhausts the specified energy budget. Further, we establish EBUA's timeliness optimality during under-loads, freedom from deadlocks, and correctness in mutually exclusive resource sharing. In particular, we prove that the algorithm's timeliness behavior subsumes the optimal timeliness behavior of deadline scheduling as a special case, and identify the conditions under which lower bounds on individual activity utilities are satisfied. In addition, we upper bound the time needed for mutually exclusively accessing shared resources under EBUA.
We conduct experimental studies by simulating the algorithm on the DVS-enabled AMD k6 processor model, and by implementing it on QNX Neutrino 6.2.1 RTOS. Our experimental results validate our analytical results. Further, they confirm EBUA's superiority over other energy-efficient real-time scheduling algorithms on timeliness and energy consumption behaviors. / Ph. D.
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Tillförlitligheten hos kliniska tester vid diagnostisering av stressfrakturer i tibia : En narrativ litteraturöversiktNordstrom, Gustav January 2024 (has links)
Bakgrund: Stressfrakturer utgör 10–20 % av alla idrottsskador och 10% av alla ortopediska skador, av samtliga stressfrakturer lokaliseras upp till 49% i tibia. För att ställa diagnosen korrekt behövs en magnetröntgen, benskanning eller datortomografi. Syfte: Syftet med denna litteraturöversikt var att kartlägga tillförlitligheten hos kliniska tester för att diagnostisera stressfrakturer i tibia. Metod: En litteraturöversikt med narrativ design tillämpades, sökningen utfördes i Pubmed, Sportdiscus, Pedro & Cinahl, inklusionskriteriet var att studierna skulle ha minst ett radiologiskt referenstest. Kvalitén av studierna bedömdes med Quadas mätinstrument. Resultat: 17 artiklar inkluderades i översikten, totalt var det åtta olika tester som undersöktes. Tre studier valde att kombinera flera tester vid diagnostiseringen av stressfrakturer i tibia. Inget ensamt test eller testkombination hade både en hög specificitet och sensitivitet. Flertalet studier fick en hög sensitivitet vid palpation, även kombinerade tester gav en hög sensitivitet. Konklusion: Enbart kliniska tester verkar inte kunna diagnostisera stressfrakturer i tibia då testerna har en låg specificitet. Eventuellt kan en kombination av tester utesluta stressfrakturer i tibia och därav minska behovet av röntgenundersökning. Flertalet studier hade metodologiska brister därför behövs mer forskning för att kunna dra säkrare slutsatser gällande testernas tillförlitlighet. / Background: Stress fractures make up 10-20% of all sports injuries and 10% of all orthopedic injuries, of all stress fractures up to 49% are in the tibia. To make the diagnosis correctly, an MRI, bone scan or computed tomography is needed. Aim: The purpose of this study was to investigate the reliability of different clinical tests in the diagnosis of stress fractures of the tibia. Method: A literature review with narrative design was applied, the search was performed in Pubmed, Sportdiscus Pedro and Cinahl, the inclusion criteria was that the studies had at least one radiological reference test. The quality of the studies was assessed with Quadas measuring instrument. Results: 17 articles were included in the review, a total of eight different test examined. Three studies chose to combine multiple tests in the diagnosis of tibial stress fractures. No single test or test combination had both a high specificity and sensitivity. Most studies obtained a high sensitivity on palpation, even combined test gave a high sensitivity. Conclusion: Clinical tests alone do not seem to be able to diagnose stress fractures in the tibia as the tests have a low specificity. Possibly, a combination of tests can rule out stress fractures in the tibia and therefore reduce the need for radiological examination. Most studies had methodological flaws therefore, more research is needed to be able to draw safer conclusions regarding the ability of the tests.
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Electronic Customer Knowledge Management Systems : a multimodal interaction approach : an empirical investigation into the role of the multimodal interaction metaphors to improve usability of Electronic Customer Knowledge Management Systems (ECKMS) and increase the user's trust, knowledge and acceptanceAlotaibi, Mutlaq Bader Gublan January 2009 (has links)
There has been an increasing demand for commercial organisations to foster real-time interaction with customers, because harnessing customer competencies has been shown to be a major contributor towards various benefits, such as growth, innovation and competition. This may drive organisations to embrace the development of multimodal interaction and complement Electronic Customer Knowledge Management Systems (E-CKMS) with metaphors of audio-visual nature. Although the implementation of E-CKMS encounters several challenges, such as lack of trust and information overload, few empirical studies were devoted to assess the role of audio-visual metaphors, and investigate whether these technologies can be put into practice. Therefore, this thesis describes a comparative evaluation study carried out to examine the implication of incorporating multimodal metaphors into E-CKMS interfaces on not only usability of E-CKMS, but also the user's trust, knowledge and acceptance. An experimental E-CKMS platform was implemented with three different modes of interaction: Visual-only E-CKMS (VCKMS) with text and graphics, Multimodal E-CKMS (MCKMS) with speech, earcons and auditory icons and Avatar-enhanced multimodal E-CKMS (ACKMS). The three platforms were evaluated by three independent groups of twenty participants each (total=60) who carried out eight common tasks of increasing complexity and design based on three different styles. Another dependent group of forty-eight participants (n=48) was instructed to interact with the systems under similar usability conditions by performing six common tasks of two styles, and fill a questionnaire devised to measure the aspects of user acceptance. The results therein revealed that ACKMS was more usable and acceptable than both MCKMS and VCKMS, whereas MCKMS was more usable than VCKMS, but less acceptable. Inferential Statistics indicated that these results were statistically significant.
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Les demandes du travail et l'épuisement émotionnel : l'influence de la qualité de la relation d'encadrement LMXHoule-Ouellette, Olivier 05 1900 (has links)
Ce mémoire vise à vérifier l’effet modérateur de la relation d’encadrement LMX sur la relation entre les demandes du travail et l’épuisement émotionnel. Nous avons d’abord étudié la relation d’encadrement LMX et ses effets multiples, particulièrement sur le stress. Nous avons envisagé le LMX comme une ressource qui peut atténuer les effets des demandes du travail (conflit, surcharge et l’ambiguïté de rôle) sur l’épuisement émotionnel, et ce, avec comme fondement théorique le modèle des tensions du travail de Karasek (1979). Pour vérifier notre modèle, nous avons procédé à une analyse secondaire de données recueillies dans le cadre provenant d’une étude précédente réalisée à l’Institut de gériatrie de l’Université de Sherbrooke en 1996. Des analyses descriptives nous ont permis de valider deux de nos trois principales hypothèses à l’effet que le LMX agit comme modérateur sur la relation entre les demandes du travail et l’épuisement émotionnel. En effet, les résultats montrent que plus le LMX est de qualité, moins les relations entre le conflit de rôle et l’épuisement émotionnel ainsi qu’entre la surcharge de rôle et l’épuisement émotionnel sont significatives. Toutefois, nos résultats indiquent que plus le LMX est de qualité, plus l’effet de l’ambiguïté de rôle est relié à l’épuisement émotionnel. / This paper will demonstrate the moderating effect of the LMX relationship on the connection between job demands and emotional exhaustion. First, we examined the LMX relationship and its various effects, especially on stress. Based on the theoretical foundations of Karasek’s workplace stress model (1979), we considered LMX as a resource that can mitigate the effects of job demands (conflict, overload and role ambiguity) on emotional exhaustion. To validate our model, we conducted a secondary analysis of data gathered in a prior study at the Université de Sherbrooke’s geriatrics institute in 1996.Descriptive analyses allowed us to validate two of our three main hypotheses to the effect that LMX functions as a moderator in the relationship between job demands and emotional exhaustion. The results showed that the better quality the LMX, the less significant the relationship between role conflict and emotional exhaustion and between role overload and emotional exhaustion. The results also showed, however, that the better quality the LMX, the greater the effect of role ambiguity on emotional exhaustion.
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Buněčná smrt jako důsledek železem indukovaného buněčného poškození / Cell death as a result of iron-induced cellular damageBěhounek, Matěj January 2016 (has links)
Iron is an essential trace element for almost all living organisms. Iron overload in cells and tissues, however, leads to their disruption. Most oftenly damaged are parenchymatic organs such as the liver, pancreas and heart. The aim of this thesis was to create cellular in vitro models for the investigation of effects of excess iron on hepatocytes and pancreatic beta cells and on these models to investigate cellular processes which lead to cellular damage during iron overload. We focused on examining the presence of oxidative and endoplasmic reticulum stress and the activation of apoptotic cell death. For our experiments, we used HEP-G2 cell line which represents human hepatocytes and NES2Y cell line which represents human pancreatic beta cells. To study the mechanisms of cellular damage during iron overload, we used two approaches by which we observed both acute and long-term effects of high levels of iron on damage of the tested cell lines. When studying the acute effect of excess iron on the cells, we applied high doses of iron (using 15 mM ferric citrate in medium) that led to the activation of cell death in hours. Long-term effects of iron overload were tested on cells regularly cultivated in the presence of 50 μM and 100 μM ferric citrate over a period of several months. Iron concentrations...
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Sítios polimórficos do gene hfe em estudos populacionais e em doenças hereditárias ou adquiridas que cursam com sobrecarga de ferro / Population study of polymorphic loci in HFE gene in hereditary or acquire disease course to iron overloadCampos, Wagner Narciso de 31 July 2013 (has links)
Mutações no gene HFE têm sido apontadas como um dos principais fatores para o desenvolvimento de sobrecarga de ferro, especialmente os SNPs (single nucleotide polymorphism) clássicos C282Y e H63D. A sobrecarga de ferro pode ser primária, atribuída diretamente a mutações do gene HFE (hemocromatose hereditária - HH) ou adquirida em decorrência de fatores genéticos e de comorbidades, particularmente, infecção pelo vírus da hepatite C (HCV) e carcinoma hepatocelular (CHC). Desequilíbrio de ligação entre os SNPs principais do gene HFE com alelos dos genes HLA-A e HLA-B podem contribuir com alterações da função das células do sistema imunológico. Neste trabalho, sequenciamos a região codificadora do gene HFE (éxon 2, 3, 4 e 5) de pacientes que apresentam ou não sobrecarga de ferro primária ou adquirida. Assim, estudamos 130 pacientes com hepatite C, 60 pacientes com CHC, 14 pacientes com HH e 100 indivíduos saudáveis. Foram encontrados sete SNPs no gene HFE no sentido 5\' para 3\': i) H63D C>G no éxon 2 (rs1799945); ii) IVS2(+4)T>C no íntron 2 (rs2071303); iii) íntron 3 C>G (rs807209); iv) C282Y G>A no éxon 4 (rs1800562); v) íntron 4 G>A (rs2794717); vi) IVS4(-44) T>C (rs1800708); vii) no íntron 5 a deleção G>del, ainda não foi descrita na literatura. Foram realizadas as reconstruções de haplótipos da região codificadora e os haplótipos estendidos englobando o gene HFE e dez outros loci (HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1, TNFa, TNFb, TNFc, TNFd e HLA-G-14pb). Também, normatizamos a nomenclatura do gene de acordo com as regras do The International ImMunoGeneTics Information System - IMGT (http://www.imgt.org/). Diversas ferramentas foram utilizadas para avaliar a associação entre os sítios polimórficos do gene HFE com a sobrecarga de ferro, incluindo testes de associações avaliando alelos, genótipos, desequilíbrio de ligação, haplótipos e diplótipos, testes de diversidades e neutralidade. Finalmente, comparamos os SNPs do gene HFE encontrados na população saudável do presente trabalho com as diversas populações mundiais, disponíveis no sítio 1000genomes (http://www.1000genomes.org/). Os resultados demonstraram que a nossa a população estava mais próxima das populações europeias e americanas, sendo parcialmente próxima das populações africanas e distante das populações asiáticas. O alelo C282Y G, contido no haplótipo da região codificadora HFE*01:03, conferiu susceptibilidade a HH na população brasileira testada, concordando com os achados observados em outras populações mundiais. O diplótipo HFE*01:02:01:01/HFE*01:01:01:05 conferiu susceptibilidade para o desenvolvimento de sobrecarga de ferro em pacientes com CHC causado pelo HCV. Detectamos forte desequilíbrio entre os alelos H63D G e IVS2(+4) C no éxon 2 do gene HFE, e concomitantemente, desequilíbrio desses alelos com alelo HLA-B*44, aparentemente, sem associação com sobrecarga de ferro, mas com aparente origem histórica. Finalmente, o teste de diversidade encontrou diferenças apenas na amostra de HH e o teste de neutralidade não encontrou pressões seletivas na população controle do presente trabalho. Concluindo, este é o primeiro trabalho, avaliando grande segmento da região codificadora do gene HFE em diversas amostras de pacientes apresentando ou não sobrecarga de ferro e em indivíduos controle. / Mutations at the HFE gene have been identified as a major factor for the development of iron overload, especially the classical single nucleotide polymorphism (SNP) C282Y and H63D. Primary iron overload can be directly attributed to mutations in the HFE gene (hereditary hemochromatosis - HH), whereas secondary overload may be acquired due to genetic factors and comorbidities, particularly infection with hepatitis C virus (HCV) and hepatocellular carcinoma (HCC). Linkage disequilibrium between major SNPs at the HFE gene with HLA-A and HLA-B alleles may contribute to alterations in the function of immune cells. We sequenced the coding region of the HFE gene (exon 2, 3, 4 and 5) of patients exhibiting primary or secondary iron overload. Thus, we studied 130 patients with hepatitis C, 60 patients with HCC, 14 patients with HH and 100 healthy individuals. We observed seven SNPs in the HFE gene in 5 \'to 3\' sequence: i) H63D C>G at exon 2 (rs1799945); ii) IVS2(+4)T>C at intron 2 (rs2071303); iii) intron 3 C>G (rs807209); iv) C282Y G>A at exon 4 (rs1800562); v) intron 4 G>A (rs2794717); vi) IVS4(-44) T>C (rs1800708); vii) at intron 5 we detected a yet undescribed G>deletion. We performed haplotype reconstruction of the coding region and extended haplotypes comprising the HFE gene and ten other loci (HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1, TNFa, TNFb, TNFc, TNFd and HLA-G14bp). In addition, we normatized the nomenclature of the HFE gene, according to the rules of the International ImMunoGeneTics Information System - IMGT (http://www.imgt.org/). Several tools were used to evaluate the association between HFE polymorphic sites with iron overload, including tests assessing associations of alleles, genotypes, linkage disequilibrium, haplotype and diplotypes, diversity and neutrality tests. Finally, we compare the SNPs at the HFE gene observed in the healthy population with those observed in diverse worldwide populations available at the 1000genomes site (http://www.1000genomes.org/) the results showed that our population was closer to American and European populations, partially close the populations of African and distant of Asian populations. The C282Y allele G, contained in the coding region HFE * 01:03 haplotype, conferred susceptibility to HH in the Brazilian population tested, agreeing with the findings observed in other worldwide populations. The HFE*01:02:01:01/HFE* 01:01:01:05 dyplotype conferred susceptibility to the development of iron overload in patients with HCC caused by HCV. A strong linkage disequilibrium was detected between the H63D G and IVS2 (+4) C alleles in exon 2 of the HFE gene, and concomitantly, a linkage between these alleles with HLA-B*44, apparently not associated with iron overload, but with apparent historical origin. Finally, the test of diversity revealed differences only in the HH sample and the neutrality test detected no selective pressures on the control population of this study. In conclusion, this is the first study evaluating a large segment of the coding region of the HFE gene in several samples of patients exhibiting or not iron overload and in control subjects.
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