954 resultados para Linear forms in logarithms


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It is becoming clear that an adequate level of long-chain highly unsaturated fatty acids in the nervous system is required for optimal function and development; however, the ability of infants to biosynthesize long-chain fatty acids is unknown. This study explores the capacity of human infants to convert 18-carbon essential fatty acids to their elongated and desaturated forms, in vivo. A newly developed gas chromatography/negative chemical ionization/mass spectrometry method employing 2H-labeled essential fatty acids allowed assessment of this in vivo conversion with very high sensitivity and selectivity. Our results demonstrate that human infants have the capacity to convert dietary essential fatty acids administered enterally as 2H-labeled ethyl esters to their longer-chain derivatives, transport them to plasma, and incorporate them into membrane lipids. The in vivo conversion of linoleic acid (18:2n6) to arachidonic acid (20:4n6) is demonstrated in human beings. All elongases/desaturases necessary for the conversion of linolenic acid (18:3n3) to docosahexaenoic acid (22:6n3) are also active in the first week after birth. Although the absolute amounts of n-3 fatty acid metabolites accumulated in plasma are greater than those of the n-6 family, estimates of the endogenous pools of 18:2n6 and 18:3n3 indicate that n-6 fatty acid conversion rates are greater than those of the n-3 family. While these data clearly demonstrate the capability of infants to biosynthesize 22:6n3, a lipid that is required for optimal neural development, the amounts produced in vivo from 18:3n3 may be inadequate to support the 22:6n3 level observed in breast-fed infants.

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SPC2 and SPC3 are two members of a family of subtilisin-related proteases which play essential roles in the processing of prohormones into their mature forms in the pancreatic B cell and many other neuroendocrine cells. To investigate the phylogenetic origins and evolutionary functions of SPC2 and SPC3 we have identified and cloned cDNAs encoding these enzymes from amphioxus (Branchiostoma californiensis), a primitive chordate. The amino acid sequence of preproSPC2 contains 689 aa and is 71% identical to human SPC2. In contrast, amphioxus prproSPC3 consists of 774 aa and exhibits 55% identity to human SPC3. These results suggest that the primary structure of SPC2 has been more highly conserved during evolution than that of SPC3. To further investigate the function(s) of SPC2 and SPC3 in amphioxus, we have determined the regional expression of these genes by using a reverse transcriptase-linked polymerase chain reaction (RT-PCR) assay. Whole amphioxus was dissected longitudinally into four equal-length segments and RNA was extracted. Using RT-PCR to simultaneously amplify SPC2 and SPC3 DNA fragments, we found that the cranial region (section 1) expressed equal amounts of SPC2 and SPC3 mRNAs, whereas in the caudal region (section 4) the SPC2-to-SPC3 ratio was 5:1. In the mid-body sections 2 and 3 the SPC2-to-SPC3 ratio was 1:5. By RT-PCR we also determined that amphioxus ILP, a homologue of mammalian insulin/insulin-like growth factor, was expressed predominately in section 3. These results suggest that the relative levels of SPC2 and SPC3 mRNAs are specifically regulated in various amphioxus tissues. Furthermore, the ubiquitous expression of these mRNAs in the organism indicates that they are involved in the processing of other precursor proteins in addition to proILP.

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A expressão emocional é um dos meios de comunicação primordiais do bebê humano, sendo sua manifestação um recurso que lhe garante a própria sobrevivência. Esta temática tem sido bastante estudada, usualmente, na relação do bebê com adultos, mais particularmente com a mãe, em condições de laboratório e ambiente doméstico. No entanto, novas configurações sociais emergiram, em que o cuidado da criança pequena tem sido cada vez mais compartilhado com instituições de educação infantil, onde os pares de idade são os parceiros mais frequentes. A revisão da literatura relacionada à expressividade emocional entre pares de bebês evidencia lacunas nesse campo, e há autores que afirmam o não reconhecimento da ocorrência mesmo da interação, já que a interação entre coetâneos nos dois primeiros anos de vida não é vista como viável. Com isso, traçamos o objetivo de verificar se ocorrem manifestações de expressividade emocional de sorriso e choro em interações de pares de bebês, no ambiente do berçário de uma creche. E, em ocorrendo, investigar como se dão. Com embasamento teórico-metodológico na Rede de Significações, realizamos um estudo longitudinal de casos múltiplos, com análise qualitativa. Participaram da pesquisa dezoito bebês de uma creche pública localizada no interior do Estado de São Paulo, e três educadoras responsáveis pela turma. Dentre os bebês, Tiago (cinco a dez meses de idade) e Bruno (oito meses a um ano e um mês de idade) foram sujeitos focais, sendo acompanhados durante cinco meses, através de videogravações semanais de trinta minutos para cada bebê. A análise do material empírico se dividiu em duas etapas: 1) mapeamento das ocorrências de sorriso e choro, discriminando os parceiros com os quais os bebês interagiram ao se expressar; e, 2) análise qualitativa dos episódios interativos nos quais Bruno e Tiago se expressaram emocionalmente com os pares. A partir das diferentes formas de expressão do bebê, tanto com base na literatura como no material empírico analisado, foram criadas as categorias de riso, sorriso, choramingo, choro e choro prolongado. Realizada a análise, não se verificou a ocorrência de risos nas interações dos bebês, pelo menos nos dias em que foram feitas as gravações. Com relação aos sorrisos de Tiago, observamos que se manifestaram em situações lúdicas, e se modificaram ao longo do tempo. Por volta dos oito / nove meses do bebê, os sorrisos passaram a ter repercussão nos parceiros, que brevemente reagiram à expressão. No caso de Bruno, também aos nove meses ele passou a manifestar alguns sorrisos que repercutiram e contagiavam os pares de idade. Os sorrisos de Bruno se manifestaram com uma riqueza de sentidos identificáveis nas interações, não sorrindo apenas aos pares, mas também dos pares e com os pares. Apesar das mudanças nos sorrisos dos bebês ao longo do tempo, o processo não se manifestou de modo linear. Nas expressões de choro dos bebês não se observou mudanças nas interações com os pares, apenas diferenças na qualidade e duração de tempo. As interações de pares em que Tiago chorou estavam relacionadas, em sua maioria, ao incômodo decorrente de invasões físicas sobre o bebê. Já no caso de Bruno, na maior parte das vezes, as interações compreendiam incômodo por situações de competição ou perda de brinquedos. Em ambas as expressões estudadas, observamos que sorrisos, apesar de menos frequentes entre os pares, contagiaram mais do que os choros, no sentido de haver alguma reação por parte dos pares. É oportuno apontar, neste momento, a relevância de estudos futuros sobre esta temática investigativa, haja vista a importância e a riqueza das manifestações de expressividade emocional nas interações de bebês que convivem em ambiente coletivo.

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A deficiência de Zn no solo causa efeitos indesejáveis na produção agrícola, pois a baixa disponibilidade deste micronutriente para as plantas promove a diminuição da atividade enzimática, além da deficiência deste elemento na alimentação, que pode levar ao estado de subnutrição. Tendo em vista a problemática do Zn no sistema solo-planta e suas variações nos compartimentos do solo, é importante a avaliação de sua fitodisponibilidade e as frações do solo que este elemento está associado. O objetivo deste trabalho foi avaliar a fitodisponibilidade e a compartimentalização de Zn no solo, para as culturas de arroz (Oryza sativa L.) e soja (Glycine max L. Merrill) e avaliar o efeito das doses de Zn sobre a nutrição e exportação deste nutriente pela cultura. Utilizou-se como plantas teste as culturas de arroz e soja para avaliar o efeito das doses de Zn sobre a nutrição e translocação deste nutriente até os grãos. Para tanto, uma amostra de um Latossolo Vermelho, textura argilosa da região de Piracicaba (SP) foi utilizada e ZnCl2 (marcado com 65Zn) como fonte. O experimento foi conduzido em casa de vegetação em DIC, com cinco doses de Zn (0, 1, 2, 4 e 8 mg kg-1 de solo), com quatro repetições. O experimento foi conduzido até a formação de grãos e foi realizada determinação de Zn por Espectrômetria de Absorção Atômica após digestão nitroperclórica e contagem do 65Zn nas partes da planta: parte aérea (PA) e panícula (P), para arroz e PA, vagem (V) e grão (G), para soja. Calculou-se a quantidade de Zn proveniente da fonte (Znpf) nas partes das plantas e o aproveitamento do Zn da fonte pelas culturas (Ap). Nas amostras de solo foram realizadas extrações por DTPA (ZnDTPA) e Mehlich-1 (ZnM1) em duas subamostragens (t1 e t2), antes da semeadura e florescimento, respectivamente. O fracionamento de Zn foi realizado em amostras de t2 nas frações: trocável (ZnTroc); ligado a carbonatos (ZnCarb); a matéria orgânica (ZnMO); a óxidos (ZnOxi) e residual (Znres). Adicionalmente, foi realizada análise do teor pseudo-total de Zn (ZnPST). Os dados obtidos foram submetidos à análise de variância pelo teste-F a 95 % de probabilidade, ajuste das variáveis em função das doses por regressões e teste de média e análises de correlações entre as principais variáveis respostas. O Zn acumulado total na planta se ajustou à regressão linear em função do aumento das doses, entretanto ao analisar as partes separadamente, só houve diferença entre as doses para a variável PA em ambas as culturas. O Znpf total nas plantas apresentou incremento com a adição das doses crescentes de Zn ao solo, entretanto, eu aproveitamento foi baixo, 12 e 8,75 % para arroz e soja, respectivamente. As doses de ZnCl2 adicionadas ao solo, aumentaram a concentração de Zn presente nas frações ZnTroc > ZnMO > ZnCarb, em ordem decrescente. O Zn total acumulado nas plantas de arroz e soja apresentam correlações crescentes para os extratores DTPA e M1 nas duas subamostragens (t1 e t2), em função das doses avaliadas. O Zn extraído pelo DTPA ou M1, apresentaram correlação significativa com o Zn extraído nas frações, na ordem decrescente, ZnTroc > ZnCarb > ZnMO

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This paper outlines the approach adopted by the PLSI research group at University of Alicante in the PASCAL-2006 second Recognising Textual Entailment challenge. Our system is composed of several components. On the one hand, the first component performs the derivation of the logic forms of the text/hypothesis pairs and, on the other hand, the second component provides us with a similarity score given by the semantic relations between the derived logic forms. In order to obtain this score we apply several measures of similitude and relatedness based on the structure and content of WordNet.

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Applied colorimetry is an important module in the program of the elective subject "Colour Science: industrial applications”. This course is taught in the Optics and Optometry Degree and it has been used as a testing for the application of new teaching and assessment techniques consistent with the new European Higher Education Area. In particular, the main objective was to reduce the attendance to lessons and encourage the individual and collective work of students. The reason for this approach is based on the idea that students are able to work at their own learning pace. Within this dynamic work, we propose online lab practice based on Excel templates that our research group has developed ad-hoc for different aspects of colorimetry, such as conversion to different colour spaces, calculation of perceptual descriptors (hue, saturation, lightness), calculation of colour differences, colour matching dyes, etc. The practice presented in this paper is focused on the learning of colour differences. The session is based on a specific Excel template to compute the colour differences and to plot different graphs with these colour differences defined at different colour spaces: CIE ΔE, CIE ΔE94 and the CIELAB colour space. This template is implemented on a website what works by addressing the student work at a proper and organized way. The aim was to unify all the student work from a website, therefore the student is able to learn in an autonomous and sequential way and in his own pace. To achieve this purpose, all the tools, links and documents are collected for each different proposed activity to achieve guided specific objectives. In the context of educational innovation, this type of website is normally called WebQuest. The design of a WebQuest is established according to the criteria of usability and simplicity. There are great advantages of using WebQuests versus the toolbox “Campus Virtual” available in the University of Alicante. The Campus Virtual is an unfriendly environment for this specific purpose as the activities are organized in different sectors depending on whether the activity is a discussion, an activity, a self-assessment or the download of materials. With this separation, it is more difficult that the student follows an organized sequence. However, our WebQuest provides a more intuitive graphical environment, and besides, all the tasks and resources needed to complete them are grouped and organized according to a linear sequence. In this way, the student guided learning is optimized. Furthermore, with this simplification, the student focuses on learning and not to waste resources. Finally, this tool has a wide set of potential applications: online courses of colorimetry applied for postgraduate students, Open Course Ware, etc.

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As has been the case with other European languages, Spanish has welcomed the arrival of English words, in spite of all purist efforts to the contrary. Moreover, it has not only adopted and adapted true Anglicisms but it has also created other forms based on English patterns, such mechanisms particularly visible in the fashion jargon in Spanish. In this paper we focus on -ing forms in the Spanish language of fashion, which may at times be genuine Anglicisms (formal or semantic ones) or false Anglicisms (analogical creations, that is, English-looking lexical elements), found in Spanish editions of fashion magazines such as Vogue, Elle, InStyle, Grazia, Glamour, and Cosmopolitan. The main aim of this study is to qualitatively analyse and classify -ing Anglicisms and false Anglicisms in the aforementioned jargon in order to establish whether the impact of English in the Spanish fashion jargon is so important as to replace native words and expressions.

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Neste artigo estuda-se a prontidão de alunos do ensino superior para a aprendizagem de álgebra linear, salientando a natureza teórica desta área de conhecimento. Participaram no estudo alunos do ensino superior, de uma turma do 1.º ano, de um Instituto Politécnico do norte de Portugal. Os alunos responderam a um teste diagnóstico, cujas questões incorporavam conteúdos lecionados durante os anos escolares anteriores à entrada no ensino superior, considerados como pré-requisito para a aprendizagem de álgebra linear numa vertente mais teórica. Dos resultados do estudo, destacam-se as grandes dificuldades dos alunos em todos os conteúdos avaliados, verificando-se que mais de metade apresentou respostas incorretas ou não respondeu às questões colocadas, donde se conclui que os alunos não apresentam um grau de prontidão adequado para aprendizagem de álgebra linear.

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The aim of my dissertation is to analyze how selected elements of language are addressed in two contemporary dystopias, Feed by M. T. Anderson (2002) and Super Sad True Love Story by Gary Shteyngart (2010). I chose these two novels because language plays a key role in both of them: both are primarily focused on the pervasiveness of technology, and on how the use/abuse of technology affects language in all its forms. In particular, I examine four key aspects of language: books, literacy, diary writing, as well as oral language. In order to analyze how the aforementioned elements of language are dealt with in Feed and Super Sad True Love Story, I consider how the same aspects of language are presented in a sample of classical dystopias selected as benchmarks: We by Yevgeny Zamyatin (1921), Brave New World by Aldous Huxley (1932), Animal Farm (1945) and Nineteen Eighty-Four (1949) by George Orwell, Fahrenheit 451 by Ray Bradbury (1952), and The Handmaid's Tale by Margaret Atwood (1986). In this way, I look at how language, books, literacy, and diaries are dealt with in Anderson’s Feed and in Shteyngart’s Super Sad True Love Story, both in comparison with the classical dystopias as well as with one another. This allows for an analysis of the similarities, as well as the differences, between the two novels. The comparative analysis carried out also takes into account the fact that the two contemporary dystopias have different target audiences: one is for young adults (Feed), whereas the other is for adults (Super Sad True Love Story). Consequently, I also consider whether further differences related to target readers affect differences in how language is dealt with. Preliminary findings indicate that, despite their different target audiences, the linguistic elements considered are addressed in the two novels in similar ways.

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Available on demand as hard copy or computer file from Cornell University Library.

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'The Chatter of the Visible' examines the paradoxical narrative features of the photo montage aesthetics of artists associated with Dada, Constructivism, and the New Objectivity.

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Variability in the test of Globorotalia menardii during the past 8 million years has been investigated at DSDP Site 502A (Caribbean Sea) and DSDP Site 503A (Eastern Equatorial Pacific). Measurements were made of spire height (delta x), maximum diameter (delta y), the tangent angles of the upper and lower peripheral keels (phi 1, phi 2, respectively), the number of chambers in the final whorl, and the area of the silhouette in keel view. Four morphotypes alpha, beta, gamma, and delta were distinguished. Morphotype alpha was found in strata ranging in age from the Late Miocene through the Holocene. It shows a continuous increase in delta x and delta y until the Late Pleistocene. During and after the final closure of the ancient Central American Seaway (between 2.4 Ma and 1.8 Ma) there was a rapid increase in the area of the test in keel view. At the Caribbean Sea site, morphotype beta evolved during the past 0.22 Ma. It is less inflated than alpha and has a more delicate test. In the morphospace of delta x vs. delta y, morphotypes alpha and beta can be distinguished by a separation line delta y = 3.2 * delta x - 160 (delta x and delta y in µm). Plots of morphotype alpha are below that line, those of beta are above it. Morphotype alpha is taken to be Globorotalia menardii menardii Parker, Jones & Brady (1865) and includes G. menardii 'A' Bolli (1970). Morphotype beta is identified as G. menardii cultrata (d'Orbigny). Morphotypes gamma and delta are extinct Upper Miocene to Pliocene forms which evolved from morphotype alpha. They have a narrower phi 1 angle and more chambers (>=7) than morphotype alpha commonly with 5 to 6 chambers (7 in transitional forms). In contemporaneous samples morphotype delta can be distinguished from gamma by a smaller value of phi 1 and 8 or more chambers in the final whorl. Morphotype gamma is taken to be G. limbata (Fornasini, 1902) and includes the junior synonym G. menardii 'B' Bolli (1970). Morphotype delta is G. multicamerata Cushman & Jarvis (1930). With the exception of the Late Pleistocene development of G. menardii cultrataonly in the Caribbean the morphological changes of G. menardii at DSDP Sites 502A and 503A are similar. The development from the ancestral G. menardii menardii of the G. limbata - G. multicamerata lineage during the Pliocene and of G. menardii cultrata during the Late Pleistocene suggests responses at the two sites to a changing palaeoceanography during and after the formation of the Isthmus of Panama.

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This study proposes gaining a new understanding of group development by considering the integrative and the punctuated equilibrium models of group development as complementary rather than competing. We hypothesized that we would observe both punctuated equilibrium and linear progression in content-analyzed data from 25 simulated project teams, albeit on different dimensions. We predicted changes in time awareness and in task and pacing activity in line with the punctuated equilibrium model and changes in structure and process on task and socioemotional dimensions in line with the integrative model. Results partially supported predictions for both models.

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Background: Previous research into age of onset in affective disorders has produced conflicting results. This paper examines the influence of heterogeneity on the age-at-first-registration distribution for the ICD-9 diagnostic group 'affective psychosis'. Method: For 1979-1991, data for age-at-first-registration for 4985 individuals diagnosed with affective psychosis (ICD-9 296.x) were extracted from a name-linked mental health register. These data were divided into (i) '296.1 only', a category used to code unipolar depression (males = 700; females = 1321); and (ii) '296 other', all 296 cases other than 296.1 (males = 1280; females = 1684). Inception rates for each 5-year age division were adjusted for the background population age-structure as a rate per 100 000 population. Results: The age-at-first-registration distribution for affective psychosis has a wide age range, with women outnumbering men. There is a near-linear increase in inception rates for both men and women with 296.1 only, while the bulk of those with affective psychoses (296 other) have an inverted U-shaped age distribution. Males have an earlier modal age-at-first-registration for 296 other compared to females. Conclusion: The heterogeneity in terms of subtypes and sex in affective psychosis clouds the interpretation of age-at-first-registration. Separating those with unipolar psychotic depression from other subclassifications and differentiating by sex may provide clues to factors that precipitate the onset of affective psychosis.

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Acoustic stimuli within the sonic range are effective triggers of C-type escape behaviours in fish. We have previously shown that fish have an acute sensitivity to infrasound also, with acceleration thresholds in the range of 10(-5) m s(-2). In addition, infrasound at high intensities around 10(-2) m s(-2) elicits strong and sustained avoidance responses in several fish species. In the present study, the possible triggering of C-escapes by infrasonic single-cycle vibrations was examined in juvenile roach Rutilus rutilus. The fish were accelerated in a controlled and quantifiable manner using a swing system. The applied stimuli simulated essential components of the accelerations that a small fish would encounter in the hydrodynamic flow field produced by a predatory fish. Typical C- and S-type escape responses were induced by accelerations within the infrasonic range with a threshold of 0.023 m s(-2) for an initial acceleration at 6.7 Hz. Response trajectories were on average in the same direction as the initial acceleration. Unexpectedly, startle behaviours mainly occurred in the trailing half of the test chamber, in which the fish were subjected to linear acceleration in combination with compression, i.e. the expected stimuli produced by an approaching predator. Very few responses were observed in the leading half of the test chamber, where the fish were subjected to acceleration and rarefaction, i.e. the stimuli expected from a suction type of predator. We conclude that particle acceleration is essential for the directionality of the startle response to infrasound, and that the response is triggered by the synergistic effects of acceleration and compression.