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383 386 Ledakis, P., Tanimura, H., Fojo, T. (1998): Limitations of Differential Display. Biochemical and Biophysical Research Communications , 251 , 653

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Hubbell, S.P., Foster, R.B., O’Brien, S.T., Harms, K.E., Condit, R., Wechsler, B., Wright, S.J. and de Lao, S.L. 1999. Light-gap disturbances, recruitment limitation, and tree diversity in a neotropical forest. Science 283: 554

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Reception studies are frequently used in audio description research to elicit preferences of the visually impaired about certain aspects and level of acceptance of various solutions. However, this research method is characterised by limitations, which are discussed in this article as regards the participants and the design of reception studies. We then present a study which we think has been successful in overcoming some of these limitations, conducted as part of the European project entitled ADLAB: Lifelong Access for the Blind on 80 visually impaired persons (VIPs) and 77 sighted controls from six project partners’ countries. The respondents were presented with various audio description solutions and answered preference, comprehension and visualisation questions to find out which solutions they preferred, how much they understood following a given description and how easy it was for them to imagine a given description. We conclude that eliciting subjective opinions of respondents might be inconclusive and that AD reception research should be more focused on the cognitive efficiency of AD.

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Advances in news gathering and dissemination technologies have made it possible that news stories are being shared simultaneously around the world. One internationally newsworthy event can generate dozens of news reports in multiple languages almost immediately by means of translation. Although news translation research has gained traction over the last 15 years, it has thus far tended to focus only on one language pair or on European language combinations because of practical limitations (e.g., language proficiency of researchers, access to content). This paper will illustrate the benefits of collaboration across languages and cultures for deepening our understanding of global news translation. To explore the possibilities as well as the limitations of this multilingual collaboration, a speech by the Japanese prime minister commemorating the 70th anniversary of Japan’s surrender ending World War II and reports about this speech in English and German media are analysed. For a detailed comparative analysis, two direct quotations from the speech were selected which were included in nearly all of the reports. We reflect on the variation identified in the news reports with reference to sources the journalists used, their own language proficiency and the potential role of an intermediary text or language.

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A 2006. évi ajánlások szerint az alapellátásban is alkalmazni kell a szérumkreatininből képlettel számított glomerulus filtrációs rátát, amely segít a krónikus vesebetegség korai felismerésében. Emiatt előtérbe kerültek a Jaffe-féle kreatininmeghatározás korlátai, és az eredmények összevethetősége érdekében felmerült az igény a leggyakrabban használt Jaffe- és az újabb kreatininmeghatározások harmonizációjára. A kinetikus Jaffe-féle kreatininmeghatározás hátránya, hogy nem elég specifikus. Ezen javítottak az elmúlt évtizedben bevezetett enzimatikus, kompenzált Jaffe és nagyfelbontású folyadékkromatográfiás módszerek. Az újabb módszerekkel kapott kreatininértékek már pontosabbak, de alacsonyabb értékük miatt a korábbi formulákkal (4 változós Modification of Diet in Renal Disease-186, Cockcroft–Gault, kvadratikus) nem lehet belőlük glomerulus filtrációs rátát számítani, mert durván torzítanák azt. Az új kreatininmódszerek miatt a korábbi számítási mód, s így a krónikus vesebetegség stádiumának meghatározása is bizonytalanná vált. Emiatt 2006-ban módosították a 4-változós Modification of Diet in Renal Disease-186 formulát, és az új (izotópdilutiós tömegspektrometriás referenciamódszerre visszavezethető) kreatininhez csak az új 4 változós Modification of Diet in Renal Disease-175 képlet ajánlott. A szerzők összevetik a kreatininmódszerek diagnosztikai értékét és korlátait.

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Traditionally, species absence in a community is ascribed either to dispersal limitation (i.e., the inability of propagules of a species to reach a site) or to habitat limitation (abiotic or biotic conditions of a site prevent species from forming a viable population); sowing experiments can then distinguish between these two mechanisms. In our view, the situation is even more complicated. To demonstrate the complexity of the problem, we designed and applied simulations based on an extension of matrix models covering effects of propagule pressure and habitat limitation, and reflecting various characteristics of a species and of a habitat. These included life history, fecundity, seed bank viability of a species, habitat carrying capacity and disturbances. All the investigated factors affected proportion of occupied habitats. Whereas they can, to a large extent, compensate for each other, simultaneous decrease of habitat suitability and propagule input can be detrimental to the survival of a population. Our model demonstrated that in many cases, the absence of a species in a community is of stochastic nature, and result of interaction of species life history and various external conditions, and thus cannot be simply attributed to a single cause. The model results are supported with examples of case studies. The results also explain some well-known ecological phenomena, as decrease of niche breadth from the center to the margins of area of distribution. Finally, the model also suggests some caveats in interpretation of the results of sowing experiments.

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The effects of elevated UV-B radiation and water limitation have been evaluated in terms of the biochemical, physiological, morphological and productivity responses of common buckwheat (Fagopyrum esculentum Moench) and tartary buckwheat (Fagopyrum tataricum Gaertn.). Research was carried out under semi-controlled conditions. Common and tartary buckwheat were exposed to UV-B radiation and water limitation in different combinations. Photosynthetic pigments, UV-absorbing compounds, potential and effective photochemical efficiency, stomatal conductance, plant morphology and biomass production were monitored. The negative effect of elevated UV-B radiation on growth parameters in common buckwheat was highly significant in watered plants but less pronounced in plants exposed to water limitation. However, in tartary buckwheat UV-B radiation mitigated the negative effects of water limitation, resulting in increased biomass production.

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Abstract  

The technique of trace element analysis by the detection of characteristic X-rays induced by high energy proton bombardment is critically examined. A discussion of the restrictions imposed by detector resolution is made, the behavior of the cross-section for X-ray production as a function of energy and atomic number is discussed. The effect of this behavior upon analysis time is demonstrated. Background is discussed in terms of its effect on the total counting rate. The use of a silicon solid state detector to determine the overlappingK-lines of light elements andL-lines of heavy elements is shown to have severe limitations. A combination of crystal monochromators and solid state detectors is suggested as a means to circumvent some of the fundamental limitations encountered with a single detector. An experimental arrangement for the use of twenty-four crystal monochromators and two solid state detectors is shown.

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Abstract  

In medical products, shelf-life after thermoplastic processing and sterilization is important, and ionizing radiation has become a preferred sterilization mode for medical devices. We have employed successfully thermal analytical methods to predict shelf-life for many polyolefin materials. However, as the material of construction becoming more sophisticated: multiphase alloys and blends, multi-layer constructions etc., issues existed that require clarification as to what extent these methodologies are applicable. We have employed thermal analytical methods in conjunction with spectroscopic and morphological methods to study the applicability and limitation of these techniques. Results were combined with real life and simulated aging experiments and presented in this article.

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Abstract  

Impact factor is a quasi-qualitative indicator, which provides a measurement of the prestige and international visibility of journals. Although the use of impact factor-based indicators for science policy purposes has increased over the last two decades, several limitations have been pointed out and should be borne in mind. The use of impact factor should be treated carefully when applied to the analysis of peripheral countries, whose national journals are hardly covered by ISI databases. Our experience in the use of impact factor based indicators for the analysis of the Spanish scientific production is shown. The usefulness of the impact factor measures in macro, meso and micro analyses is displayed. In addition, the main advantages, such as the great accessibility of impact factor and its ready-to-use nature are pointed out. Several limitations such as the need to avoid inter-field comparisons or the convenience of using a fixed journal set for international comparisons are also stressed. It is worth noting that the use of impact factor in the research evaluation process has influenced strongly the publication strategy of scientists.

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