640 resultados para Diallel crosses


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The aim of the present study was to propose and evaluate the use of factor analysis (FA) in obtaining latent variables (factors) that represent a set of pig traits simultaneously, for use in genome-wide selection (GWS) studies. We used crosses between outbred F2 populations of Brazilian Piau X commercial pigs. Data were obtained on 345 F2 pigs, genotyped for 237 SNPs, with 41 traits. FA allowed us to obtain four biologically interpretable factors: ?weight?, ?fat?, ?loin?, and ?performance?. These factors were used as dependent variables in multiple regression models of genomic selection (Bayes A, Bayes B, RR-BLUP, and Bayesian LASSO). The use of FA is presented as an interesting alternative to select individuals for multiple variables simultaneously in GWS studies; accuracy measurements of the factors were similar to those obtained when the original traits were considered individually. The similarities between the top 10% of individuals selected by the factor, and those selected by the individual traits, were also satisfactory. Moreover, the estimated markers effects for the traits were similar to those found for the relevant factor.

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The study of photophysical and photochemical processes crosses the interest of many fields of research in physics, chemistry and biology. In particular, the photophysical and photochemical reactions, after light absorption by a photosynthetic pigment-protein complex, are among the fastest events in biology, taking place on timescales ranging from tens of femtoseconds to a few nanoseconds. Among the experimental approaches developed for this purpose, the advent of ultrafast transient absorption spectroscopy has become a powerful and widely used technique.[1,2] Focusing on the process of photosynthesis, it relies upon the efficient absorption and conversion of the radiant energy from the Sun. Chlorophylls and carotenoids are the main players in the process. Photosynthetic pigments are typically arranged in a highly organized fashion to constitute antennas and reaction centers, supramolecular devices where light harvesting and charge separation take place. The very early steps in the photosynthetic process take place after the absorption of a photon by an antenna system, which harvests light and eventually delivers it to the reaction center. In order to compete with internal conversion, intersystem crossing, and fluorescence, which inevitably lead to energy loss, the energy and electron transfer processes that fix the excited-state energy in photosynthesis must be extremely fast. In order to investigate these events, ultrafast techniques down to a sub-100 fs resolution must be used. In this way, energy migration within the system as well as the formation of new chemical species such as charge-separated states can be tracked in real time. This can be achieved by making use of ultrafast transient absorption spectroscopy. The basic principles of this notable technique, instrumentation, and some recent applications to photosynthetic systems[3] will be described. Acknowledgements M. Moreno Oliva thanks the MINECO for a “Juan de la Cierva-Incorporación” research contract. References [1] U. Megerle, I. Pugliesi, C. Schriever, C.F. Sailer and E. Riedle, Appl. Phys. B, 96, 215 – 231 (2009). [2] R. Berera, R. van Grondelle and J.T.M. Kennis, Photosynth. Res., 101, 105 – 118 (2009). [3] T. Nikkonen, M. Moreno Oliva, A. Kahnt, M. Muuronen, J. Helaja and D.M. Guldi, Chem. Eur. J., 21, 590 – 600 (2015).

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This work is a discussion of the artistic process of an artist-researcher made from field research with benzedeiras and benzedores the state of Rio Grande do Norte. This is an investigation on the cultural universe of the popular benzeção as poetic element to the artistic dance. To discuss the different stages of the research and the relationships between the artist-researcher, the benzedeiras/benzedores and the creation/composition scenic, the work takes as reference the triangular relationship created by anthropologist Claude Lévi-Strauss, in his discussion on the effectiveness of symbols of healing, adapted to the context of benzeção . For dialogue between tradition, popular knowledge, scientific and artistic knowledge this work approaches as analytical reference the epistemological model of the type rhizome proposed by Deleuze and Guattari, understanding it as a model that seeks to form a network of relations in different paths of research, to establish connections between elements without target them or subordinating them. In the universe of benzeção , benzedeiras and benzedores carry a symbolic power that issued in whispered prayers, in peculiar gestures that form crosses in space, heal those who seek your prayers and blessing. In this research, the mixture of popular knowledge, artistic and academic knowledge, born an artistic work in the context of Performing Arts, more specifically dance, and between branches, saints, candles and conversations the work allowed other looks poetic for our popular culture, (re)asserting their cultural and human values through the art

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Mode of access: Internet.

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Melanocytes, pigment-producing cells, derive from the neural crest (NC), a population of pluripotent cells that arise from the dorsal aspect of the neural tube during embryogenesis. Many genes required for melanocyte development were identified using mouse pigmentation mutants. The deletion of the transcription factor Ets1 in mice results in hypopigmentation; nevertheless, the function of Ets1 in melanocyte development is unknown. The goal of the present study was to establish the temporal requirement and role of Ets1 in murine melanocyte development. In the mouse, Ets1 is widely expressed in developing organs and tissues, including the NC. In the chick cranial NC, Ets1 is required for the expression of Sox10, a transcription factor critical for the development of melanocytes, enteric ganglia, and other NC derivatives. Using a combination of immunofluorescence and cell survival assays Ets1 was found to be required between embryonic days 10 and 11, when it regulates NC cell and melanocyte precursor (melanoblast) survival. Given the requirement of Ets1 for Sox10 expression in the chick cranial NC, a potential interaction between these genes was investigated. Using genetic crosses, a synergistic genetic interaction between Ets1 and Sox10 in melanocyte development was found. Since Sox10 is essential for enteric ganglia formation, the importance of Ets1 on gut innervation was also examined. In mice, Ets1 deletion led to decreased gut innervation, which was exacerbated by Sox10 heterozygosity. At the molecular level, Ets1 was found to activate a Sox10 enhancer critical for Sox10 expression in melanoblasts. Furthermore, mutating Ets1 at a site I characterized in the spontaneous variable spotting mouse pigmentation mutant, led to a 2-fold decrease in enhancer activation. Overexpression and knockdown of Ets1 did not affect Sox10 expression; nonetheless, Ets1 knockdown led to a 6-fold upregulation of the transcription factor Sox9, a gene required for melanocyte and chondrocyte development, but which impairs melanocyte development when its expression is prolonged. Together, these results suggest that Ets1 is required early during melanocyte development for NC cell and melanoblast survival, possibly acting upstream of Sox10. The transcription factor Ets1 may also act indirectly in melanocyte fate specification by repressing Sox9 expression, and consequently cartilage fate.

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Arguably, the catalyst for the best research studies using social analysis of discourse is personal ‘lived’ experience. This is certainly the case for Kamada, who, as a white American woman with a Japanese spouse, had to deal first hand with the racialization of her son. Like many other mixed-ethnic parents, she experienced the shock and disap-pointment of finding her child being racialized as ‘Chinese’ in America through peer group taunts, and constituted as gaijin (a foreigner) in his own homeland of Japan. As a member of an e-list of the (Japan) Bilingualism Special Interest Group (BSIG), Kamada learnt that other parents from the English-speaking foreign community in Japan had similar disturbing stories to tell of their mixed-ethnic children who, upon entering the Japanese school system, were mocked, bullied and marginalized by their peers. She men-tions a pervasive Japanese proverb which warns of diversity or difference getting squashed: ‘The nail that sticks up gets hammered down’. This imperative to conform to Japanese behavioural and discursive norms prompted Kamada’s quest to investigate the impact of ‘otherization’ on the identities of children of mixed parentage. In this fascinat-ing book, she shows that this pressure to conform is balanced by a corresponding cele-bration of ‘hybrid’ or mixed identities. The children in her study are also able to negotiate their identities positively as they come to terms with contradictory discursive notions of ‘Japaneseness’, ‘whiteness’ and ‘halfness/doubleness’.The discursive construction of identity has become a central concern amongst researchers across a wide range of academic disciplines within the humanities and the social sciences, and most existing work either concentrates on a specific identity cate-gory, such as gender, sexuality or national identity, or else offers a broader discussion of how identity is theorized. Kamada’s book is refreshing because it crosses the usual boundaries and offers divergent insights on identity in a number of ways. First, using the term ‘ethno-gendering’, she examines the ways in which six mixed-ethnic girls living in Japan accomplish and manage the relationship between their gender and ethnic ‘differ-ences’ from age 12 to 15. She analyses in close detail how their actions or displays within certain situated interactions might come into conflict with how they are seen or constituted by others. Second, Kamada’s study builds on contemporary writing on the benefits of hybridity where identities are fluid, flexible and indeterminate, and which contest the usual monolithic distinctions of gender, ethnicity, class, etc. Here, Kamada carves out an original space for her findings. While scholars have often investigated changing identities and language practices of young people who have been geographi-cally displaced and are newcomers to the local language, Kamada’s participants were all born and brought up in Japan, were fluent in Japanese and were relatively proficient in English. Third, the author refuses to conceptualize or theorize identity from a single given viewpoint in preference to others, but in postmodernist spirit draws upon multiple perspectives and frameworks of discourse analysis in order to create different forms of knowledge and understandings of her subject. Drawing on this ‘multi-perspectival’ approach, Kamada examines grammatical, lexical, rhetorical and interactional features from six extensive conversations, to show how her participants position their diverse identities in relation to their friends, to the researcher and to the outside world. Kamada’s study is driven by three clear aims. The first is to find out ‘whether there are any tensions and dilemmas in the ways adolescent girls of Japanese and “white” mixed parentage in Japan identify themselves in terms of ethnicity’. In Chapter 4, she shows how the girls indeed felt that they stood out as different and consequently experienced isolation, marginalization and bullying at school – although they were able to make better sense of this as they grew older, repositioning the bullies as pitiable. The second aim is to ask how, if at all, her participants celebrate their ethnicity, and furthermore, what kind of symbolic, linguistic and social capital they were able to claim for themselves on the basis of their hybrid identities. In Chapter 5, Kamada shows how the girls over time were able to constitute themselves as insiders while constituting ‘the Japanese’ as outsiders, and their network of mixed-ethnic friends was a key means to achieve this. In Chapter 6, the author develops this potential celebration of the girls’ mixed ethnicity by investigating the privileges they perceived it afforded them – for example, having the advantage of pos-sessing English proficiency and intercultural ‘savvy’ in a globalized world. Kamada’s third aim is to ask how her participants positioned themselves and performed their hybrid identities on the basis of their constituted appearance: that is, how the girls saw them-selves based on how they looked to others. In Chapter 7, the author shows that, while there are competing discourses at work, the girls are able to take up empowering positions within a discourse of ‘foreigner attractiveness’ or ‘a white-Western female beauty’ discourse, which provides them with a certain cachet among their Japanese peers. Throughout the book, Kamada adopts a highly self-reflexive perspective of her own position as author. For example, she interrogates the fact that she may have changed the lived reality of her six participants during the course of her research study. As the six girls, who were ‘best friends’, lived in different parts of the Morita region of Japan, she had to be proactive in organizing six separate ‘get-togethers’ through the course of her three-year study. She acknowledges that she did not collect ‘naturally occurring data’ but rather co-constructed opportunities for the girls to meet and talk on a regular basis. At these meetings, she encouraged the girls to discuss matters of identity, prompted by open-ended interview questions, by stimulus materials such as photos, articles and pic-tures, and by individual tasks such as drawing self-portraits. By giving her participants a platform in this way, Kamada not only elicited some very rich spoken data but also ‘helped in some way to shape the attitudes and self-images of the girls positively, in ways that might not have developed had these get-togethers not occurred’ (p. 221). While the data she gathers are indeed rich, it may well be asked whether there is a mismatch between the girls’ frank and engaging accounts of personal experience, and the social constructionist academic register in which these are later re-articulated. When Kamada writes, ‘Rina related how within the more narrow range of discourses that she had to draw on in her past, she was disempowered and marginalized’ (p. 118), we know that Rina’s actual words were very different. Would she really recognize, understand and agree with the reported speech of the researcher? This small omission of self-reflexivity apart – an omission which is true of most lin-guistic ethnography conducted today – Kamada has written a unique, engaging and thought-provoking book which offers a model to future discourse analysts investigating hybrid identities. The idea that speakers can draw upon competing discourses or reper-toires to constitute their identities in contrasting, creative and positive ways provides linguistic researchers with a clear orientation by which to analyse the contradictions of identity construction as they occur across time in different discursive contexts

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This study examines the long profiles of tributaries of the Tejo (Tagus) and Zêzere rivers in central eastern Portugal (West Iberia) in order to provide new insights into the patterns, timing and controls on drainage development during the Pleistocene to Holocene incision stage. The long profiles were extracted from lower order tributary streams associated with the trunk drainage of the Tejo River and one main tributary, the Zêzere River (Fig. 1). These streams flow through a landscape strongly influenced by variations in bedrock lithology (mainly granites and metasediments), fault structures delimiting crustal blocks with distinct uplift rates, and a base-level lowering history (tectonic uplift / eustatic). The long profiles of the tributaries of the Tejo and Zêzere rivers record a series of transient and permanent knickpoints. The permanent knickpoints have direct correlation with the bedrock strength, corresponding to the outcropping of very hard quartzites or to the transition from softer (slates/metagreywaques) to harder (granite) basement. The analyzed streams/rivers record also an older transient knickpoint/knickzone separating: a) an upstream relict graded profile, with lower steepness and higher concavity, that reflects a long period of quasi-equilibrium conditions reached after the beginning of the incision stage; and b) a downstream reach displaying a rejuvenated long profile, with steeper gradient and lower concavity, particularly for the final segment, which is often convex (Fig. 2). The rejuvenated reaches testify the upstream propagation of several incision waves that are the response of each stream to continuous or increasing crustal uplift and dominant periods of base-level lowering by the trunk drainages, coeval of low sea level conditions. The long profiles and their morphological configurations enabled spatial and relative temporal patterns of incision to be quantified for each individual tributary stream. The incision values of streams flowing in uplifted blocks of the Portuguese Central Range (PCR) (ca.380-280 m) indicate differential uplift and are higher than the incision values of streams flowing on the adjacent South Portugal planation surface – the Meseta (ca. 200 m). The normalized steepness index, calculated using the method of Wobus et al. (2006), proved to be sensitive to active tectonics, as lower ksn values were found in relict graded profiles of streams located in less uplifted blocks, (e.g. Sertã stream in the PCR), or in those flowing through tectonic depressions. Fig. 1 – Geological map of the study area. 1 – fluvial terraces (Pleistocene); 2 – sedimentary cover (Paleogene and Neogene); 3 – slates and metasandstones (Devonian); 4 – slates and quartzites (Silurian); 5 – quartzites (Ordovician); 6 – slates and metagreywackes (Precambrian to Cambrian); 7 – slates, metagreywackes and limestones (Precambrian); 8 – granites and ortogneisses; 9 – diorites and gabros; 10 - fault. SFf – Sobreira Formosa fault; Sf – Sertã fault; Pf – Ponsul fault; Gf – Grade fault. The differential uplift indicated by the distribution of the ksn values and by the fluvial incision was likely accumulated on a few major faults, as the Sobreira Formosa fault (SFf), thus corroborating the tectonic activity of these faults. Due to the fact that the relict graded profiles can be correlated with other geomorphic references documented in the study area, namely the T1 terrace of the Tagus River (with an age of ca. 1 Myr), the following incision rates can be estimated: a) for the studied streams located in uplifted blocks of the PCR, 0.38 m/kyr to 0.28 m/kyr; b) for the streams flowing on the South Portugal planation surface, 0.20 m/kyr. The differential uplift inferred between crustal blocks in the study area corroborates the neotectonic activity of the bordering faults, which has been proposed in previous studies based upon less robust data. Fig. 2 – Longitudinal profile of the Nisa stream a tributary of the Tejo River. Note the equilibrium relict profile upstream the older transient knickpoint (hatched line) and the downstream rejuvenated profile (continuous line). Legend: tKP – transient knickpoint; rKp – resistant knickpoint; Mt – schist and phyllite; Gr – granite; Hf – hornfels; Og – orthogneisse. In the inset Distance – Slope plots, fill circles correspond to the relict graded profile, crosses correspond to the rejuvenated profile located downstream the older transient knickpoint (tKP).

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Resumo: A procura por carne de qualidade tem proporcionado ao setor de ovinocultura a adoção por técnicas de produção que possam contribuir para disponibilizar ao mercado produtos que atendam as necessidades dos consumidores, que se tornam cada vez mais exigentes quanto à aquisição de produtos que possam trazer benefícios a saúde. Assim, objetivou-se determinar a qualidade da carne de ovinos puros e cruzados criados no semiárido Nordestino. Utilizaram-se 30 cordeiros machos e fêmeas, oriundos dos cruzamentos Morada Nova x Morada Nova, Rabo Largo x Morada Nova e Santa Inês x Morada Nova, alojados em baias e alimentados com dieta a base de capim Canarana, milho farelo de soja e calcário. Os animais foram abatidos com peso médio de 24 kg de peso vivo e as carcaças mantidas em câmara frigorífica a 4?C, por 24 horas. Após esse período, foi seccionado o músculo Longissimus dorsi que foi embalado, identificado e armazenado a 20?C. Foram determinados os atributos físicos de capacidade de retenção de água, perda de peso por cocção e força de cisalhamento; os atributos químicos como umidade, proteína, cinza, lipídios e colesterol; avaliações subjetivas da carcaça como cor, marmoreio, textura da carne, distribuição da gordura, espessura da gordura e área de olho de lombo; os sensoriais de dureza, suculência, sabor, aroma e aceitação global e o perfil de ácidos graxos. O delineamento utilizado foi em esquema fatorial 3x2 (três grupos genéticos e dois sexos) e as médias comparadas pelo teste de Duncan a 5%. Não houve diferença (p>0,05) entre os genótipos para a composição química da carne, exceto para a variável lipídio (p<0,05). Para as características subjetivas da carcaça o genótipo influenciou (p<0,05) nas variáveis cor, marmoreio e textura da carne. O genótipo promoveu efeito (p<0,05) para as características físicas de capacidade de retenção de água e perda de peso por cocção. Os atributos sensoriais não sofreram efeitos (p>0,05) dos genótipos avaliados. Os genótipos influenciaram (p<0,05) as concentrações dos ácidos graxos saturados, monoinsaturados e poli-insaturados assim como, nas relações ?3:?6 e AGM:AGS. O fator sexo influenciou (p<0,05) nas variáveis umidade, força de cisalhamento, dureza, ácidos graxos desejáveis e relação ?3:?6. O cruzamento entre raças nativas mostrou-se com potencial para a produção de carne de qualidade, a raça Morada Nova melhorou os atributos físico-químicos da carne e em seu perfil lipídico e, o fator sexo melhorou o atributo maciez dando destaque a carne das fêmeas. Abstract: The demand for quality meat products has given the sheep industry sector productions techniques that can contribute providing the market with products that supply the needs of consumers require, who are becoming more demanding as the acquisition of differentiated and bring health benefits. The objective was to evaluate the quality of the pure sheep meat and cross bred in the semiarid Northeast of Brazil. It was used 30 male lambs and female, that came from crosses Morada Nova x Morada Nova, Rabo Largo x Morada Nova and Santa Ines x Morada Nova, housed in pens and fed a diet of grass Canarana, corn soybean meal and limestone. The animals were slaughtered at average weight of 24 kg, live weight, and carcasses kept in refrigeration chamber at 4 ° C for 24 hours. After this period the Longissimus dorsi muscle was selected, packaged, labeled and stored at 20˚C. The physical attributes were determined such as water holding capacity, cooking weight loss and shear force; the chemical attributes such as moisture, protein, ash, lipids and cholesterol; Subjective evaluations such as color, marbling, meat texture, fat distribution, fat thickness and loin eye area; the hardness sensory, juiciness, flavor, aroma and global acceptance and fatty acid profile. The design was a 3x2 factorial arrangement (three genetic groups and two genders) and the measures compared by Duncan test at 5%. There was no difference (p> 0.05) between genotypes for the chemical composition of meat, except for the lipid variable (p <0.05). To the subjective characteristics of the carcass, the genotype influenced (p <0.05) in the variables color, marbling and meat texture. The genotype promoted significant effect (p <0.05) for the physical characteristics, water retention capacity and weight loss on cooking. The sensory attributes did not suffer significant effects (p> 0.05) of the evaluated genotypes. The genotypes influenced (p <0.05) in the concentrations of saturated fatty acids, monounsaturated and polyunsaturated as well as in the relations ω3: ω6 and AGM:AGS. The gender factor influenced (P <0.05) in the variables moisture, shear strength, hardness, desirable fatty acids and relation ω3: ω6. The cross between native breeds showed up with potential for quality meat production, the Morada Nova improved the physical and chemical attributes of the flesh and in their lipid profiles and sex factor improved softness attribute highlighting the meat of females.

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The lack of pear-compatible rootstocks in Brazil calls for the application of classical genetic techniques. Therefore, in order to obtain select suitable material, the search for genetic segregation must be continuous, being used as alternative scion cultivars. This study aims to assess fruit set, number of seeds, fruit weight and fruit diameter according to crosses between pear cultivars. The trial was carried out from September 2008 to February 2009 in a commercial orchard in the city of Vacaria/RS, Brazil. For the pollination process, pollen was extracted from flowers at full-white stage in the same orchard. The cultivars used were 'Packham's Triumph' and 'Clapps Favorite'. The crossings were defined as: open pollination; selfpollination of 'Packham's Triumph' and 'Packham's Triumph' × 'Clapps Favorite'. The pollinations were done manually in flowers at full-white stage, which were opened, emasculated and then pollinated. Each pollinated flower was then isolated with a fine nylon bag. Open pollination and cross pollination between 'Packham's Triumph' × 'Clapps Favorite' provided higher fruit set (17 and 18%, respectively). Fruit weight and diameter did not differ between treatments. Open pollination provided fruits with a higher number of seeds.

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The central question of this article follows: “is a style issue inherent to language activity?”, and this question crosses with several other experiences with many linguistic enunciates like the one in the following ad: “Vem pra caixa você também. Vem!” (You should also come to Caixa. Come now!). Would enunciates like these be the owners of style? In order to adequately comprehend what style is, it is necessary to fix the surging of stylistics, to verify the conceptual path of style and, only after this verification, to seek answers for the above-mentioned question