219 research outputs found

    Binocular coordination: reading stereoscopic sentences in depth

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    The present study employs a stereoscopic manipulation to present sentences in three dimensions to subjects as they read for comprehension. Subjects read sentences with (a) no depth cues, (b) a monocular depth cue that implied the sentence loomed out of the screen (i.e., increasing retinal size), (c) congruent monocular and binocular (retinal disparity) depth cues (i.e., both implied the sentence loomed out of the screen) and (d) incongruent monocular and binocular depth cues (i.e., the monocular cue implied the sentence loomed out of the screen and the binocular cue implied it receded behind the screen). Reading efficiency was mostly unaffected, suggesting that reading in three dimensions is similar to reading in two dimensions. Importantly, fixation disparity was driven by retinal disparity; fixations were significantly more crossed as readers progressed through the sentence in the congruent condition and significantly more uncrossed in the incongruent condition. We conclude that disparity depth cues are used on-line to drive binocular coordination during reading.<br/

    Kemungkinan Kehadiran Sistiserkus/cacing taenia saginata taiwanensis di Bali

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    Telah dilakukan suatu penelitian pendahuluan untuk mengetahui kemungkinan adanya sistiserkus atau cacing Taenia saginata taiwanensis di Bali. Pengamatan dilakukanterhadap adanya infeksi sistiserkus secara alami pada hati 638 ekor babi yang dipotong di RPH Denpasar , dari bulan Juni sampai Juli 1993.Bintik-bintik kecil kekuningan atau putih susu, yang diduga merupakan kista T.s. taiwanensis, ditemukan pada 146 hati babi (22,88%). Setiap hati yang terinfeksi mengandung 1 - 6 kista, yang menyebar secara acak di masing-masing lobus. Kebanyakan kista yang ditemukan telah mengalami degenerasi (66.43%) atau kalsifikasi (32.8%). Satu kista mature yang ditemukan (0.7%) dari hati yang positif, ternyata mengandung skoleks taenia yang diperlengkapi dengan kait-kait. Temuan ini menunjukkan kemungkinan adanya sisteserkus cacing Ts. taiwanensis di Bali sebab hati babi bukanlah tempat predileksi utama sistiserkus cacing Taenia solium

    Skyrmions from a Born-Infeld Action

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    We consider a geometrically motivated Skyrme model based on a general covariant kinetic term proposed originally by Born and Infeld. We introduce this new term by generalizing the Born-Infeld action to a non-abelian SU(2)SU(2) gauge theory and by using the hidden gauge symmetry formalism. The static properties of the Skyrmion are then analyzed and compared with other Skyrme-like models.Comment: 11 pages, 4 figures (not included), revtex v3, LAVAL-PHY-11-9

    Transcription factor mediated control of anthocyanin biosynthesis in vegetative tissues

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    Plants accumulate secondary metabolites to adapt to environmental conditions. These compounds, here exemplified by the purple-colored anthocyanins, are accumulated upon high temperatures, UV-light, drought, and nutrient deficiencies, and may contribute to tolerance to these stresses. Producing compounds is often part of a more broad response of the plant to changes in the environment. Here we investigate how a transcription-factor-mediated program for controlling anthocyanin biosynthesis also has effects on formation of specialized cell structures and changes in the plant root architecture. A systems biology approach was developed in tomato (Solanum lycopersicum) for coordinated induction of biosynthesis of anthocyanins, in a tissue- and development-independent manner. A transcription factor couple from Antirrhinum that is known to control anthocyanin biosynthesis was introduced in tomato under control of a dexamethasone-inducible promoter. By application of dexamethasone, anthocyanin formation was induced within 24 h in vegetative tissues and in undifferentiated cells. Profiles of metabolites and gene expression were analyzed in several tomato tissues. Changes in concentration of anthocyanins and other phenolic compounds were observed in all tested tissues, accompanied by induction of the biosynthetic pathways leading from Glc to anthocyanins. A number of pathways that are not known to be involved in anthocyanin biosynthesis were observed to be regulated. Anthocyanin-producing plants displayed profound physiological and architectural changes, depending on the tissue, including root branching, root epithelial cell morphology, seed germination, and leaf conductance. The inducible anthocyanin-production system reveals a range of phenomena that accompanies anthocyanin biosynthesis in tomato, including adaptions of the plants architecture and physiology

    Identifiability of Biologicals in Adverse Drug Reaction Reports Received From European Clinical Practice

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    Biologicals are established treatment options that require pharmacovigilance adapted to their specific nature, including the need for products to be identifiable up to the specific manufacturer in reports of adverse drug reactions (ADRs). This study explored the identifiability of 10 classes of similar and related biologicals up to the level of the manufacturer in ADR reports received from European clinical practice between 2011 and June 2016. Adequate identifiers were reported for 96.7% of the suspected biologicals, ranging from 89.5% for filgrastim to 99.8% for interferon beta‐1a. The product identifiability remained consistently high over time for classes of biologicals for which biosimilars were introduced during follow‐up. The overall batch traceability was, however, only ensured for 20.5% of the suspected biologicals and needs further improvement. This study shows that the European system for identification of ADRs to the level of the manufacturer is robust, allowing for the timely detection of potential product‐specific safety signals for biologicals

    Assessing the benefits of stereoscopic displays to visual search: methodology and initial findings

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    Visual search is a task that is carried out in a number of important security and health related scenarios (e.g., X-ray baggage screening, radiography). With recent and ongoing developments in the technology available to present images to observers in stereoscopic depth, there has been increasing interest in assessing whether depth information can be used in complex search tasks to improve search performance. Here we outline the methodology that we developed, along with both software and hardware information, in order to assess visual search performance in complex, overlapping stimuli that also contained depth information. In doing so, our goal is to foster further research along these lines in the future. We also provide an overview with initial results of the experiments that we have conducted involving participants searching stimuli that contain overlapping objects presented on different depth planes to one another. Thus far, we have found that depth information does improve the speed (but not accuracy) of search, but only when the stimuli are highly complex and contain a significant degree of overlap. Depth information may therefore aid real-world search tasks that involve the examination of complex, overlapping stimuli

    Net positive outcomes for nature

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    Much research and policy effort is being expended on seeking ways to conserve living nature while enabling the economic and social development needed to increase global equity and end poverty. We propose that this will only be possible if the language of policy shifts away from setting conservation targets that focus on avoiding losses and towards developing processes that consider net outcomes for biodiversity

    Global existence for a system of non-linear and non-local transport equations describing the dynamics of dislocation densities

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    In this paper, we study the global in time existence problem for the Groma-Balogh model describing the dynamics of dislocation densities. This model is a two-dimensional model where the dislocation densities satisfy a system of transport equations such that the velocity vector field is the shear stress in the material, solving the equations of elasticity. This shear stress can be expressed as some Riesz transform of the dislocation densities. The main tool in the proof of this result is the existence of an entropy for this syste

    Modeling the Subsurface Structure of Sunspots

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    While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseismology to probe the internal structure with sufficient confidence to distinguish between the monolith and cluster models, the development of physically realistic sunspot models are a priority for helioseismologists. This is because they are not only important indicators of the variety of physical effects that may influence helioseismic inferences in active regions, but they also enable detailed assessments of the validity of helioseismic interpretations through numerical forward modeling. In this paper, we provide a critical review of the existing sunspot models and an overview of numerical methods employed to model wave propagation through model sunspots. We then carry out an helioseismic analysis of the sunspot in Active Region 9787 and address the serious inconsistencies uncovered by \citeauthor{gizonetal2009}~(\citeyear{gizonetal2009,gizonetal2009a}). We find that this sunspot is most probably associated with a shallow, positive wave-speed perturbation (unlike the traditional two-layer model) and that travel-time measurements are consistent with a horizontal outflow in the surrounding moat.Comment: 73 pages, 19 figures, accepted by Solar Physic
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