847 resultados para Dominance and diversity


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Rapport de stage présenté à la Faculté des Arts et Sciences en vue de l’obtention du grade de Maître des Sciences (M. Sc.) en Criminologie, Option Stage en Intervention

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TET2 is a tumor suppressor gene that has been implicated in the epigenetic regulation of gene expression. Inactivating TET2 mutations are common in MDS. These mutations may contribute to early clonal dominance and myeloid transformation, although the exact mechanisms remain to be elucidated. Common to the environment of MDS are elevations in cytokines, such as TNFα and IFN-γ. It was hypothesized that inflammatory cytokines TNF-α and IFN-γ may promote clonal expansion of TET2 mutant progenitors. Adult (10-14 weeks-old) Tet2 wild type (+/+) and Tet2 mutant (-/-) C57BL/6 mice strains were chosen as a model system. Lineage negative cells (Lin-), enriched for hematopoietic stem and progenitor cells, were isolated from Tet2 +/+ and -/- bone marrow and cultured in the absence or presence of varying concentrations of TNFα or IFN-γ in methylcellulose colony formation assays and long term cell culture assays, over a period of 12 and 30 days respectively, and their colony growth, cell count, immunophenotype and resistance to apoptosis were examined. Where indicated, serial re-plating was performed. Expression of apoptotic regulators was assessed by qRT-PCR. In the triplicate experiments, starting with equal densities of Tet2 +/+ and -/- Lin- cells, Tet2 -/- Lin- cells displayed increased resistance to cytokine-induced growth suppression and superior colony forming ability over +/+ in the serial re-plating assays under stress of increasing TNFα or IFN γ. Tet2 -/- progenitors also displayed a lower apoptotic index compared to +/+ under stress of increasing TNFα, suggesting increased resistance to TNFα induced apoptosis. Transcriptional data showed low expression of Tnfr1, Fas and caspase 8, as well as a high expression of Bcl-2 and Iap1 in Tet2 -/- compared to +/+ under stress of TNFα. Tet2-/- also showed increased basal expression of endogenous TNFα mRNA compared to +/+. In the human colony growth assay, the clonal growth of TET2 mutant CFU-GM progenitors was enhanced at low TNFα concentrations. Conclusion: Mutations that promote resistance to environmental stem cell stressors are a known mechanism of clonal selection in aplastic anaemia and JAK2-mutant MPN and our findings suggest that this mechanism may be critical to clonal selection and dominance in MDS.

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Over the past decades, vegetation and climate have changed significantly in the Arctic. Deciduous shrub cover is often assumed to expand in tundra landscapes, but more frequent abrupt permafrost thaw resulting in formation of thaw ponds could lead to vegetation shifts towards graminoid-dominated wetland. Which factors drive vegetation changes in the tundra ecosystem are still not sufficiently clear. In this study, the dynamic tundra vegetation model, NUCOM-tundra (NUtrient and COMpetition), was used to evaluate the consequences of climate change scenarios of warming and increasing precipitation for future tundra vegetation change. The model includes three plant functional types (moss, graminoids and shrubs), carbon and nitrogen cycling, water and permafrost dynamics and a simple thaw pond module. Climate scenario simulations were performed for 16 combinations of temperature and precipitation increases in five vegetation types representing a gradient from dry shrub-dominated to moist mixed and wet graminoid-dominated sites. Vegetation composition dynamics in currently mixed vegetation sites were dependent on both temperature and precipitation changes, with warming favouring shrub dominance and increased precipitation favouring graminoid abundance. Climate change simulations based on greenhouse gas emission scenarios in which temperature and precipitation increases were combined showed increases in biomass of both graminoids and shrubs, with graminoids increasing in abundance. The simulations suggest that shrub growth can be limited by very wet soil conditions and low nutrient supply, whereas graminoids have the advantage of being able to grow in a wide range of soil moisture conditions and have access to nutrients in deeper soil layers. Abrupt permafrost thaw initiating thaw pond formation led to complete domination of graminoids. However, due to increased drainage, shrubs could profit from such changes in adjacent areas. Both climate and thaw pond formation simulations suggest that a wetter tundra can be responsible for local shrub decline instead of shrub expansion.

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Background: Disease flares of established atopic dermatitis (AD) are generally associated with a low-diversity skin microbiota and Staphylococcus aureus dominance. The temporal transition of the skin microbiome between early infancy and the dysbiosis of established AD is unknown. Methods: We randomly selected 50 children from the Cork Babies After SCOPE: Evaluating the Longitudinal Impact Using Neurological and Nutritional Endpoints (BASELINE) longitudinal birth cohort for microbiome sampling at 3 points in the first 6 months of life at 4 skin sites relevant to AD: the antecubital and popliteal fossae, nasal tip, and cheek. We identified 10 infants with AD and compared them with 10 randomly selected control infants with no AD. We performed bacterial 16S ribosomal RNA sequencing and analysis directly from clinical samples. Results: Bacterial community structures and diversity shifted over time, suggesting that age strongly affects the skin microbiome in infants. Unlike established AD, these patients with infantile AD did not have noticeably dysbiotic communities before or with disease and were not colonized by S aureus. In comparing patients and control subjects, infants who had affected skin at month 12 had statistically significant differences in bacterial communities on the antecubital fossa at month 2 compared with infants who were unaffected at month 12. In particular, commensal staphylococci were significantly less abundant in infants affected at month 12, suggesting that this genus might protect against the later development of AD. Conclusions: This study suggests that 12-month-old infants with AD were not colonized with S aureus before having AD. Additional studies are needed to confirm whether colonization with commensal staphylococci modulates skin immunity and attenuates development of AD.

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Rapport de stage présenté à la Faculté des Arts et Sciences en vue de l’obtention du grade de Maître des Sciences (M. Sc.) en Criminologie, Option Stage en Intervention

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Coral reefs can exist as coral- and macroalgae-dominated habitats often separated by only a few hundred metres. While herbivorous fish are known to depress the abundance of algae and help maintain the function of coral-dominated habitats, less is known about their influence in algae-dominated habitats. Here, we quantified herbivorous fish and benthic algal communities over a 6 mo period in coral-dominated (back-reef) and algal-dominated (lagoon) habitats in a relatively undisturbed fringing coral reef (Ningaloo, Western Australia). Simulta - neously, we tested the effects of herbivorous fish on algal recruitment in both habitats using recruitment tiles and fish exclusion cages. The composition of established algal communities differed consistently between habitats, with the back-reef hosting a more diverse community than the Sargassum-dominated lagoon. However, total algal biomass and cover only differed between habitats in autumn, coinciding with maximum Sargassum biomass. The back-reef hosted high coral cover and a diverse herbivorous fish community, with herbivore biomass an order of magnitude greater than the lagoon. Despite these differences in herbivore composition, exclusion of large herbivores had a similar positive effect to foliose macroalgae recruitment on experimental tiles in both back-reef and lagoon habitats. Additionally, territorial damselfish found in the backreef increased turf algae cover and decreased crustose coralline algae cover on recruitment tiles. Collectively, our results show that disparate herbivorous fish communities in coral- and algaedominated habitats are similarly able to limit the recruitment of foliose macroalgae, but suggest that when herbivorous fish biomass and diversity are relatively low, macroalgal communities are able to escape herbivore control through increased growth.

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Facial attractiveness is a particularly salient social cue that influences many important social outcomes. Using a standard key-press task to measure motivational salience of faces and an old/new memory task to measure memory for face photographs, this thesis investigated both within-woman and between-women variations in response to facial attractiveness. The results indicated that within-woman variables, such as fluctuations in hormone levels, influenced the motivational salience of facial attractiveness. However, the between-women variable, romantic relationship status, did not appear to modulate women’s responses to facial attractiveness. In addition to attractiveness, dominance also contributed to both the motivational salience and memorability of faces. This latter result demonstrates that, although attractiveness is an important factor for the motivational salience of faces, other factors might also cause faces to hold motivational salience. In Chapter 2, I investigated the possible effects of women’s salivary hormone levels (estradiol, progesterone, testosterone, and estradiol-to-progesterone ratio) on the motivational salience of facial attractiveness. Physically attractive faces generally hold greater motivational salience, replicating results from previous studies. Importantly, however, the effect of attractiveness on the motivational salience of faces was greater in test sessions where women had high testosterone levels. Additionally, the motivational salience of attractive female faces was greater in test sessions where women had high estradiol-to-progesterone ratios. While results from Chapter 2 suggested that the motivational salience of faces was generally positively correlated with their physical attractiveness, Chapter 3 explored whether physical characteristics other than attractiveness contributed to the motivational salience of faces. To address this issue, I first had the faces rated on multiple traits. Principal component analysis of third-party ratings of faces for these traits revealed two orthogonal components that were highly correlated with trustworthiness and dominance ratings respectively. Both components were positively and independently related to the motivational salience of faces. While Chapter 2 and 3 did not examine the between-woman differences in response to facial attractiveness, Chapter 4 examined whether women’s responses to facial attractiveness differed as a function of their romantic partnership status. As several researchers have proposed that partnership status influences women’s perception of attractiveness, in Chapter 4 I compared the effects of men’s attractiveness on partnered and unpartnered women’s performance on two response measures: memory for face photographs and the motivational salience of faces. Consistent with previous research, women’s memory was poorer for face photographs of more attractive men and more attractive men’s faces held greater motivational salience. However, in neither study were the effects of attractiveness modulated by women’s partnership status or partnered women’s reported commitment to or happiness with their romantic relationship. A key result from Chapter 4 was that more attractive faces were harder to remember. Building on this result, Chapter 5 investigated the different characteristics that contributed to the memorability of face photographs. While some work emphasizes relationships with typicality, familiarity, and memorability ratings, more recent work suggests that ratings of social traits, such as attractiveness, intelligence, and responsibility, predict the memorability of face photographs independently of typicality, familiarity, and memorability ratings. However, what components underlie these traits remains unknown, as well as whether these components relate to the actual memorability of face photographs. Principal component analysis of all these face ratings produced three orthogonal components that were highly correlated with trustworthiness, dominance, and memorability ratings, respectively. Importantly, each of these components also predicted the actual memorability of face photographs.

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Es necesario que los gerentes sean líderes y establezcan relaciones sólidas con los empleados, para luego establecer las mismas con socios potenciales. Para lograr este objetivo, Con el fin de cumplir este objetivo, el uso de estrategias y técnicas de negociación es crucial, así como la importancia de la conciencia cultural y de la diversidad. La globalización no sólo ha movido a los mercados sino también a las personas, la inmigración es un fenómeno fuerte hoy en día y varios países, como Canadá, han sido inclusivos y han apoyado a estos nuevos ciudadanos. Las empresas de Canadá, sin importar la industria, han asumido el reto de integrar una fuerza laboral diversa con el propósito de adquirir nuevos conocimientos y crecer a nivel nacional, pero sobre todo en el ámbito internacional. Igualmente, es esencial tener en cuenta las ventajas y limitaciones del multiculturalismo dentro de la empresa y específicamente en las negociaciones interculturales.

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Changing the traditional pattern of public procurement for an electronic paradigm is a radical innovation involving major organizational changes, the breaking up of traditional processes and practices, obsolescence of knowledge and skills. Going beyond the European Commission's recommendations, in 2009 Portugal pioneered in making e-procurement mandatory in the pre-award phase, in a European context of multiple technical standards and lack of interoperability of electronic platforms across the EU countries. Six years later, when the creation of a European e-procurement single market is a EU mission and a major legislative amendment is underway in Portugal, this study looks at the relationship between e-procurement and innovation in the Portuguese municipalities aiming to understand the extent into which the adoption of e-procurement embraced a real organizational change or, on the other hand, if it just represented a mere adaptation of the usual procurement practices. The study draws on data from an electronic survey to all municipalities in mainland Portugal and the analysis is mainly descriptive and exploratory. The paradigm shift in public procurement involves major organizational changes but, overall, the results suggest that most municipalities do not have a clear understanding of the innovative scope (depth and diversity) implied by e-procurement. E-procurement shows advantages over the paper-based model but an unbalanced perception of the innovation dimensions has influenced the implementation of e-procurement and the degree of organizational change.

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Fleas, several aeroallergens as well as many food allergens are the most common allergenic sources for animals and frequent cause of allergic reactions with different target organs such as skin, eyes, and respiratory or digestive systems. Allergy diagnosis needs to follow well-established guidelines under clinical and laboratory approaches. Since 1980 with the Hanifin & Rajka’s criteria for the diagnosis of atopic dermatitis (AD) in humans, successive proposals have been developed to identify atopic dermatitis in dogs. A consensual plan was first proposed by Willemse in 1986 undergoing several modifications in 1994. Prélaud and colleagues made important changes to the plan in 1998 and it was further adjusted by Favrot in 2009. In 2010, this plan was approved by the International Task Force on Canine Atopic Dermatitis (CAD). It was subjected in 2015 to minor updates with regard to therapeutic options. To improve diagnostic accuracy by integrating the basic knowledge on sensitization development and allergen nature and diversity, allergen sources and implicated molecular allergens for animals should be clearly identified. As well as in human medicine, this molecular epidemiology concept is essential for the veterinary allergy diagnosis in the near future, standing as the basis of a component-resolved diagnosis (CRD). Besides current pharma- cotherapy, it will be highly relevant to increase the efficiency of the avoidance measures and specific immunotherapy. Clinical guidelines will lead to at least 80 % of positive diagnosis of atopy, but newer laboratory methods in veterinary medicine aiming to a more precise diagnosis and a better integration of the clinical/laboratory diagnostic course are needed. Allergoms identification for animals, from different allergen sources proteoms should become a priority in veterinary allergology, in order to allow the intended CRD, which is essential to understand the cross-reaction phenomena, allowing a more precise and possibly effective component-resolved immunotherapy (CRIT). Further research has been carried out for a better understanding of the interaction between allergic clinical condition and immune pathophysiology. As well as in human medicine, a deeper knowledge of the molecular immunological mechanisms in veterinary allergy — with their specific allergen triggers — will also provide the veterinary allergist with the necessary information to act more efficiently in the future.

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This paper describes working and living conditions of persons within diplomatic services from the perspective of stress and demands. The conditions of stress and demands described in this article are similar for leaders, volunteers, actors of international agencies and nongovernmental organizations. Scope and diversity of diplomatic tasks and connected psychsocial stress will be outlined. Families of diplomates are also affected. Mental health problems in the diplomatic corps are known, but they are considered as a taboo issue. Consequently, the basis of empirical research and literature is limited. It is mentioned that expatriates, migrants, refugees and students in foreign countries can develop similar problems. The role of psychology and psychotherapeutic interventions are discussed.

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This paper describes working and living conditions of persons within diplomatic services from the perspective of stress and demands. The conditions of stress and demands described in this article are similar for leaders, volunteers, actors of international agencies and nongovernmental organizations. Scope and diversity of diplomatic tasks and connected psychsocial stress will be outlined. Families of diplomates are also affected. Mental health problems in the diplomatic corps are known, but they are considered as a taboo issue. Consequently, the basis of empirical research and literature is limited. It is mentioned that expatriates, migrants, refugees and students in foreign countries can develop similar problems. The role of psychology and psychotherapeutic interventions are discussed.

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Principal Topic: ''In less than ten years music labels will not exist anymore.'' Michael Smelli, former Global COO Sony/BMG MCA/QUT IMP Business Lab Digital Music Think Thanks 9 May 2009, Brisbane Big music labels such as EMI, Sony BMG and UMG have been responsible for promoting and producing a myriad of stars in the music industry over the last decades. However, the industry structure is under enormous threat with the emergence of a new innovative era of digital music. Recent years have seen a dramatic shift in industry power with the emergence of Napster and other file sharing sites, iTunes and other online stores, iPod and the MP3 revolution. Myspace.com and other social networking sites are connecting entrepreneurial artists with fans and creating online music communities independent of music labels. In 2008 the digital music business internationally grew by around 25% to 3.7 Billion US-Dollar. Digital platforms now account for around 20% of recorded music sales, up from 15 % in 2007 (IFPI Digital music report 2009). CD sales have fallen by 40% since their peak levels. Global digital music sales totalled an estimated US$ 3 Billion in 2007, an increase of 40% on 2006 figures. Digital sales account for an estimated 15% of global market, up from 11% in 2006 and zero in 2003. The music industry is more advanced in terms of digital revenues than any other creative or entertainment industry (except games). Its digital share is more than twice that of newspapers (7%), films (35) or books (2%). All these shifts present new possibilities for music entrepreneurs to act entrepreneurially and promote their music independently of the major music labels. Diffusion of innovations has a long tradition in both sociology (e.g. Rogers 1962, 2003) and marketing (Bass 1969, Mahajan et al., 1990). The context of the current project is theoretically interesting in two respects. First, the role of online social networks replaces traditional face-to-face word of mouth communications. Second, as music is a hedonistic product, this strongly influences the nature of interpersonal communications and their diffusion patterns. Both of these have received very little attention in the diffusion literature to date, and no studies have investigated the influence of both simultaneously. This research project is concerned with the role of social networks in this new music industry landscape, and how this may be leveraged by musicians willing to act entrepreneurially. Our key research question we intend to address is: How do online social network communities impact the nature, pattern and speed that music diffuses? Methodology/Key Propositions : We expect the nature/ character of diffusion of popular, generic music genres to be different from specialized, niche music. To date, only Moe & Fader (2002) and Lee et al. (2003) investigated diffusion patterns of music and these focus on forecast weekly sales of music CDs based on the advance purchase orders before the launch, rather than taking a detailed look at diffusion patterns. Consequently, our first research questions are concerned with understanding the nature of online communications within the context of diffusion of music and artists. Hence, we have the following research questions: RQ1: What is the nature of fan-to-fan ''word of mouth'' online communications for music? Do these vary by type of artist and genre of music? RQ2: What is the nature of artist-to-fan online communications for music? Do these vary by type of artist and genre of music? What types of communication are effective? Two outcomes from research social network theory are particularly relevant to understanding how music might diffuse through social networks. Weak tie theory (Granovetter, 1973), argues that casual or infrequent contacts within a social network (or weak ties) act as a link to unique information which is not normally contained within an entrepreneurs inner circle (or strong tie) social network. A related argument, structural hole theory (Burt, 1992), posits that it is the absence of direct links (or structural holes) between members of a social network which offers similar informational benefits. Although these two theories argue for the information benefits of casual linkages, and diversity within a social network, others acknowledge that a balanced network which consists of a mix of strong ties, weak ties is perhaps more important overall (Uzzi, 1996). It is anticipated that the network structure of the fan base for different types of artists and genres of music will vary considerably. This leads to our third research question: RQ3: How does the network structure of online social network communities impact the pattern and speed that music diffuses? The current paper is best described as theory elaboration. It will report the first exploratory phase designed to develop and elaborate relevant theory (the second phase will be a quantitative study of network structure and diffusion). We intend to develop specific research propositions or hypotheses from the above research questions. To do so we will conduct three focus group discussions of independent musicians and three focus group discussions of fans active in online music communication on social network sites. We will also conduct five case studies of bands that have successfully built fan bases through social networking sites (e.g. myspace.com, facebook.com). The idea is to identify which communication channels they employ and the characteristics of the fan interactions for different genres of music. We intend to conduct interviews with each of the artists and analyse their online interaction with their fans. Results and Implications : At the current stage, we have just begun to conduct focus group discussions. An analysis of the themes from these focus groups will enable us to further refine our research questions into testable hypotheses. Ultimately, our research will provide a better understanding of how social networks promote the diffusion of music, and how this varies for different genres of music. Hence, some music entrepreneurs will be able to promote their music more effectively. The results may be further generalised to other industries where online peer-to-peer communication is common, such as other forms of entertainment and consumer technologies.

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Balimau Putih [an Indonesian cultivar tolerant to rice tungro bacilliform virus (RTBV)] was crossed with IR64 (RTBV, susceptible variety) to produce the three filial generations F1, F2 and F3. Agroinoculation was used to introduce RTBV into the test plants. RTBV tolerance was based on the RTBV level in plants by analysis of coat protein using enzyme-linked immunosorbent assay. The level of RTBV in cv. Balimau Putih was significantly lower than that of IR64 and the susceptible control, Taichung Native 1. Mean RTBV levels of the F1, F2 and F3 populations were comparable with one another and with the average of the parents. Results indicate that there was no dominance and an additive gene action may control the expression of tolerance to RTBV. Tolerance based on the level of RTBV coat protein was highly heritable (0.67) as estimated using the mean values of F3 lines, suggesting that selection for tolerance to RTBV can be performed in the early selfing generations using the technique employed in this study. The RTBV level had a negative correlation with plant height, but positive relationship with disease index value

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This paper sets out to examine from published literature and crash data analyses whether alcohol in bicycle crashes is an issue about which we should be concerned. It discusses factors that have the potential to increase the number of bicycle crashes in which alcohol is involved (such growth in the size and diversity of the cyclist population, and balance and coordination demands) and factors which may reduce the importance of alcohol in bicycle crashes (such as time of data factors and child riders). It also examines data availability issues that contribute to difficulties in determining the true magnitude of the issue. Methods: This paper reviews previous research and reports analyses of data from Queensland, Australia, that examine the role of alcohol in Police-reported road crashes. In Queensland it is an offence to ride a bicycle or drive a motor vehicle with a BAC exceeding 0.05% (or lower for novice and professional drivers). Results: In the five years 2003-2007, alcohol was reported as involved in 165 bicycle crashes (4%). The bicycle rider was coded as “under the influence” or “over the prescribed BAC limit” in 15 were single unit crashes (12%). In multi-vehicle bicycle crashes, alcohol involvement was reported for 16 cyclists (0.4%) and 110 operators of other vehicles (3%). Additional analyses including characteristics of the cyclist crashes involving alcohol and the importance of missing data will be discussed in the paper. Conclusion: The increase in participation in cycling and the vulnerability of cyclists to injuries support the need to examine the role of alcohol in bicycle crashes. Current data suggest that alcohol on the part of the vehicle driver is a larger concern than alcohol on the part of the cyclist, but improvements in data collection are needed before more precise conclusions can be drawn.