959 resultados para Arabic language--Semantics--Early works to 1800
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The Saccharomyces cerevisiae Rlp7 protein has extensive identity and similarity to the large ribosomal subunit L7 proteins and shares an RNA-binding domain with them. Rlp7p is not a ribosomal protein; however, it is encoded by an essential gene and therefore must perform a function essential for cell growth. In this report, we show that Rlp7p is a nucleolar protein that plays a critical role in processing of precursors to the large ribosomal subunit RNAs. Pulse–chase labeling experiments with Rlp7p-depleted cells reveal that neither 5.8SS, 5.8SL, nor 25S is produced, indicating that both the major and minor processing pathways are affected. Analysis of processing intermediates by primer extension indicates that Rlp7p-depleted cells accumulate the 27SA3 precursor RNA, which is normally the major substrate (85%) used to produce the 5.8S and 25S rRNAs, and the ratio of 27SBL to 27SBS precursors changes from approximately 1:8 to 8:1 (depleted cells). Because 27SA3 is the direct precursor to 27SBS, we conclude that Rlp7p is specifically required for the 5′ to 3′ exonucleolytic trimming of the 27SA3 into the 27SBS precursor. As it is essential for processing in both the major and minor pathways, we propose that Rlp7p may act as a specificity factor that binds precursor rRNAs and tethers the enzymes that carry out the early 5′ to 3′ exonucleolytic reactions that generate the mature rRNAs. Rlp7p may also be required for the endonucleolytic cleavage in internal transcribed spacer 2 that separates the 5.8S rRNA from the 25S rRNA.
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Barley (Hordeum vulgare L.) plants were grown at different photon flux densities ranging from 100 to 1800 μmol m−2 s−1 in air and/or in atmospheres with reduced levels of O2 and CO2. Low O2 and CO2 partial pressures allowed plants to grow under high photosystem II (PSII) excitation pressure, estimated in vivo by chlorophyll fluorescence measurements, at moderate photon flux densities. The xanthophyll-cycle pigments, the early light-inducible proteins, and their mRNA accumulated with increasing PSII excitation pressure irrespective of the way high excitation pressure was obtained (high-light irradiance or decreased CO2 and O2 availability). These findings indicate that the reduction state of electron transport chain components could be involved in light sensing for the regulation of nuclear-encoded chloroplast gene expression. In contrast, no correlation was found between the reduction state of PSII and various indicators of the PSII light-harvesting system, such as the chlorophyll a-to-b ratio, the abundance of the major pigment-protein complex of PSII (LHCII), the mRNA level of LHCII, the light-saturation curve of O2 evolution, and the induced chlorophyll-fluorescence rise. We conclude that the chlorophyll antenna size of PSII is not governed by the redox state of PSII in higher plants and, consequently, regulation of early light-inducible protein synthesis is different from that of LHCII.
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This thesis contains a translatological analysis of the Spanish proverbs collected by Charles Cahier in Quelque six mille proverbes et aphorismes usuels empruntés à notre âge et aux siècles derniers. Proverbs and other sententious sayings are part of our day-to-day life, and are more or less intensely used according to cultures and their types of speech. They have always existed in every single civilisation. There is, indeed, no denying that the purpose of proverbs is to convey an old experience. They are quoted by major philosophers and writers of all times. As a result of the interest they have raised, books of proverbs have been published for many centuries in a high number of countries. Proverbs can be found everywhere, both in professional and personal settings, or in a conversation between friends. In France, these sayings are more commonly used in literature than in spoken language, whereas in Spain proverbs can be found at all levels of communication. In this regard, it is interesting to compare the translations of international works to detect a number of misunderstandings regarding the interpretation of paremiological elements. This is why translating proverbs is a genuine, complex issue. This thesis, which is aimed at Spanish and French speakers (including native and foreign speakers), has a double application (translatological and linguistic) and falls within the context of translatological and comparative paremiology...
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Pese a los progresos logrados en la protección de los derechos fundamentales de salud y educación de las personas sordas usuarias de las lenguas de signos, a menudo se sigue negando a niños sordos su derecho a aprender y usar las lenguas de signos en su educación y en entornos físicos y psicosociales accesibles de conformidad con la Convención de los Derechos de las Personas con Discapacidad (CDPD) y con las recientes leyes 27/2007 y 17/2007. El objetivo principal de este estudio fue obtener información sobre los factores estratégicos que favorecen una escuela saludable e inclusiva, mediante programas de educación bilingüe sostenibles y de calidad para escolares sordos en España. La metodología utilizada consistió en un estudio descriptivo con componentes de investigación-acción participativa y un enfoque de análisis estratégico. Como resultados, cabe destacar que las principales macrotendencias que, en el ámbito internacional, han promovido el cambio hacia prácticas bilingües son dos: en primer lugar, los cambios sociales y políticos que tienden a una creciente aceptación de la diversidad y los temas relacionados con las personas sordas; y en segundo lugar, una tendencia a un activismo, una autoconciencia y un apoderamiento crecientes por parte de las personas sordas. Como contrapartida, las que lo han obstaculizado son, por un lado, la visión de la sordera como una condición médica, que puede solucionarse mediante la tecnología; y por otro lado, el fonocentrismo, unido a una cierta resistencia social a lo desconocido. Aunque en España algunas de las escuelas que han iniciado el cambio cumplen las recomendaciones de la CDPD, la mayoría están todavía en una fase preliminar de formulación o puesta en práctica de este nuevo modelo y distan mucho de encontrarse distribuidas de manera igualitaria en las diferentes comunidades autónomas. Como conclusión podemos decir que conseguir una educación más saludable e inclusiva para los escolares sordos implica poner en marcha una estrategia de actuación planificada en la que participen activamente todos los sectores y organismos relevantes implicados y, en particular, las comunidades sordas a través de las organizaciones que las representan. Sin un cambio radical de perspectiva, la salud y la educación no serán accesibles a todos y las desigualdades sociales se verán acentuadas.
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In this study, a digital CMOS camera was calibrated for use as a non-contact colorimeter for measuring the color of granite artworks. The low chroma values of the granite, which yield similar stimulation of the three color channels of the camera, proved to be the most challenging aspect of the task. The appropriate parameters for converting the device-dependent RGB color space into a device-independent color space were established. For this purpose, the color of a large number of Munsell samples (corresponding to the previously defined color gamut of granite) was measured with a digital camera and with a spectrophotometer (reference instrument). The color data were then compared using the CIELAB color formulae. The best correlations between measurements were obtained when the camera works to 10-bits and the spectrophotometric measures in SCI mode. Finally, the calibrated instrument was used successfully to measure the color of six commercial varieties of Spanish granite.
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Population synthesis studies constitute a powerful method to reconstruct the birth distribution of periods and magnetic fields of the pulsar population. When this method is applied to populations in different wavelengths, it can break the degeneracy in the inferred properties of initial distributions that arises from single-band studies. In this context, we extend previous works to include X-ray thermal emitting pulsars within the same evolutionary model as radio-pulsars. We find that the cumulative distribution of the number of X-ray pulsars can be well reproduced by several models that, simultaneously, reproduce the characteristics of the radio-pulsar distribution. However, even considering the most favourable magneto-thermal evolution models with fast field decay, lognormal distributions of the initial magnetic field overpredict the number of visible sources with periods longer than 12 s. We then show that the problem can be solved with different distributions of magnetic field, such as a truncated lognormal distribution, or a binormal distribution with two distinct populations. We use the observational lack of isolated neutron stars (NSs) with spin periods P > 12 s to establish an upper limit to the fraction of magnetars born with B > 1015 G (less than 1 per cent). As future detections keep increasing the magnetar and high-B pulsar statistics, our approach can be used to establish a severe constraint on the maximum magnetic field at birth of NSs.
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Terminologists’ interest in studying the role of metaphor and metaphorical terms in specialized communication has proliferated since the first papers addressing this issue appeared in the 1990s. However, we believe that some facets of terminological meaning still remain overlooked or merit further analysis. This paper attempts to contribute to the study of one of these facets: the figurative meaning of some compound terms used in the domain of luxury marketing and business. In order to present a systematized view of this phenomenon we will adopt some theoretical tools from the Conventional Figurative Language Theory, in order to confirm the validity of some of its postulates for compound term analysis. Next, a contrastive approach between English, Spanish and Russian compound terms will put the theoretical ideas into practice with the aim of illustrating their applied and metalinguistic potential. Some basic conclusions will be offered at the end of the paper.
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The last few years have witnessed the exponential growth of platforms like Uber and Airbnb and the creation of countless other less well-known examples. The expansion of the on-demand economy puts huge pressure on regulators to adapt it to the existing frameworks for labour and taxation. The rapid growth of the sector also divides experts: it is seen by many as threat for working conditions, and by others as an incredible opportunity. The purpose of this essay is to take a balanced perspective on what we know about the on-demand economy and what needs further investigation. More research is needed on the individual cases before one can draw conclusions on how this new sector works. The political economy of the sector is made even more interesting by the fact that the technology is developing faster than the regulation. Yet, our plea to policy-makers is to refrain from legislating too early and to take the time to understand how the supply and the demand of these services behave and their equilibrium.
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Software erosion can be controlled by periodically checking for consistency between the de facto architecture and its theoretical counterpart. Studies show that this process is often not automated and that developers still rely heavily on manual reviews, despite the availability of a large number of tools. This is partially due to the high cost involved in setting up and maintaining tool-specific and incompatible test specifications that replicate otherwise documented invariants. To reduce this cost, our approach consists in unifying the functionality provided by existing tools under the umbrella of a common business-readable DSL. By using a declarative language, we are able to write tool-agnostic rules that are simple enough to be understood by non-technical stakeholders and, at the same time, can be interpreted as a rigorous specification for checking architecture conformance
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The lifespan of plants ranges from a few weeks in annuals to thousands of years in trees. It is hard to explain such extreme longevity considering that DNA replication errors inevitably cause mutations. Without purging through meiotic recombination, the accumulation of somatic mutations will eventually result in mutational meltdown, a phenomenon known as Muller’s ratchet. Nevertheless, the lifespan of trees is limited more often by incidental disease or structural damage than by genetic aging. The key determinants of tree architecture are the axillary meristems, which form in the axils of leaves and grow out to form branches. The number of branches is low in annual plants, but in perennial plants iterative branching can result in thousands of terminal branches. Here, we use stem cell ablation and quantitative cell-lineage analysis to show that axillary meristems are set aside early, analogous to the metazoan germline. While neighboring cells divide vigorously, axillary meristem precursors maintain a quiescent state, with only 7–9 cell divisions occurring between the apical and axillary meristem. During iterative branching, the number of branches increases exponentially, while the number of cell divisions increases linearly. Moreover, computational modeling shows that stem cell arrangement and positioning of axillary meristems distribute somatic mutations around the main shoot, preventing their fixation and maximizing genetic heterogeneity. These features slow down Muller’s ratchet and thereby extend lifespan.
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Mode of access: Internet.
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Includes indexes.
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Mode of access: Internet.
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"Comparative table of the MSS. and editions": v. 1, p. [xxxvi]
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Mode of access: Internet.