38 research outputs found

    How strongly do word reading times and lexical decision times correlate? Combining data from eye movement corpora and megastudies

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    We assess the amount of shared variance between three measures of visual word recognition latencies: eye movement latencies, lexical decision times and naming times. After partialling out the effects of word frequency and word length, two well-documented predictors of word recognition latencies, we see that 7-44% of the variance is uniquely shared between lexical decision times and naming times, depending on the frequency range of the words used. A similar analysis of eye movement latencies shows that the percentage of variance they uniquely share either with lexical decision times or with naming times is much lower. It is 5 – 17% for gaze durations and lexical decision times in studies with target words presented in neutral sentences, but drops to .2% for corpus studies in which eye movements to all words are analysed. Correlations between gaze durations and naming latencies are lower still. These findings suggest that processing times in isolated word processing and continuous text reading are affected by specific task demands and presentation format, and that lexical decision times and naming times are not very informative in predicting eye movement latencies in text reading once the effect of word frequency and word length are taken into account. The difference between controlled experiments and natural reading suggests that reading strategies and stimulus materials may determine the degree to which the immediacy-of-processing assumption and the eye-mind assumption apply. Fixation times are more likely to exclusively reflect the lexical processing of the currently fixated word in controlled studies with unpredictable target words rather than in natural reading of sentences or texts

    Fulminant hyperpyrexia induced by bleomycin

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    Mild and self-limiting fever following bleomycin use is common, and a fatal hyperpyrexial response occurs rarely. In previously reported cases, such hyperpyrexia occurred either after the initial administration of the drug or during subsequent therapy following an initial pyrexial response. We describe a fatal hyperpyrexial reaction after bleomycin in a patient with T-cell lymphoma who had had no febrile response when she received her initial injection 3 weeks earlier. Since the occurrence of this hyperpyrexial response is unpredictable, health care workers as well as patients and relatives should always be alert to this potentially lethal complication and prompt measures should be taken in any patient who develops fever after bleomycin use.published_or_final_versio

    Photometry and surface physical properties of comet 19P/Borrelly

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    The successful Deep Space 1 flyby of Comet P/19 Borrelly offers an unprecedented opportunity to perform disk-resolved photometry and photometric modeling of a comet's nucleus. The flyby occurred at a favorable ground-based apparition, enabling concomitant telescopic observations that provided both the "big picture" in time and space and observations at photometric viewing geometries not attained by the spacecraft. The solar phase angle of the encounter period changed from 87 to 52 degrees over a period of 1.5 hours; this range is ideal for determining the macroscopic roughness of the comet's surface. The microphysical texture of the surface is best determined by ground based observations at aphelion and near opposition. The combination of both disk resolved measurements from DS1 and disk integrated measurements from both DS1 and the ground permits a constrained set of photometric parameters to be derived. Preliminary analysis of the global geometric albedo yields a value at V wavelengths (550 nm) between 0.031 +/- 0.005 (for a Mathilde-type solar phase curve at phase angles less than 10 degrees) and 0.042 +/- 0.005 (for an average C-type phase curve). Albedo variegations of at least a factor of two exist on Borrelly's surface: Its light curve amplitude of nearly a magnitude may thus not be due to shape alone. The image resolution of 60 m allows mapping of albedo variegations in terms of active jet morphology. Funded by NASA

    Imaging Borrelly

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    The nucleus, coma, and dust jets of short-period Comet 19P/Borrelly were imaged from the Deep Space 1 spacecraft during its close flyby in September 2001. A prominent jet dominated the near-nucleus coma and emanated roughly normal to the long axis of nucleus from a broad central cavity. We show it to have remained fixed in position for more than 34 hr, much longer than the 26-hr rotation period. This confirms earlier suggestions that it is co-aligned with the rotation axis. From a combination of fitting the nucleus light curve from approach images and the nucleus' orientation from stereo images at encounter, we conclude that the sense of rotation is right-handed around the main jet vector. The inferred rotation pole is approximately perpendicular to the long axis of the nucleus, consistent with a simple rotational state. Lacking an existing IAU comet-specific convention but applying a convention provisionally adopted for asteroids, we label this the north pole. This places the sub-solar latitude at ~60° N at the time of the perihelion with the north pole in constant sunlight and thus receiving maximum average insolation

    Observations of comet 19P/Borrelly from the Miniature Integrated Camera and Spectrometer (MICAS) aboard Deep Space 1

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    Images from the DS1 MICAS CCD camera reveal in three dimensions, the complex characteristics of Borrelly's nucleus, coma, and jets. The images acquired during the last 2 hours of the approach, as the nucleus became resolved and grew to roughly 150 pixels in length, provide stereo coverage of both the nucleus and inner coma over a wide range of phase angle and exposure time. The principal structure in the coma is a sunward-pointed collimated jet that is also visible in ground-based images. This jet is canted about 30 degrees off the sun line and appears to be roughly aligned with the local vertical at the surface from where it originates. Long-exposure images reveal details of the structure of the inner coma. They show the jet, visible at long range, to be composed of at least three discrete components whose locations evidently correspond to specific surface features. The elongated nucleus exhibits topographically distinct terrains and strong albedo variegations (of at least a factor of 2). The jets emanate from within the brighter smoother rolling plains. A consistent model is that the main jets are co-aligned with the rotation axis of the nucleus and issue from regions on the plains that are currently in constant sunlight. The other major terrain is a rough unit that is darker than the average, includes even darker isolated spots, and appears as a jumbled topography. Other surface features include parallel ridges, crater-like depressions, numerous narrow dark fracture-like features, and areas of mottled albedo. However no small fresh impact craters are evident attesting to a geologically young, actively evolving surface

    9969 Braille: Deep Space 1 infrared spectroscopy, geometric albedo, and classification

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    Spectra of Asteroid 9969 Braille in the 1.25–2.6 µm region returned by the Deep Space 1 (DS1) Mission show a ~10% absorption band centered at 2 µm, and a reflectance peak at 1.6 µm. Analysis of these features suggest that the composition of Braille is roughly equal parts pyroxene and olivine. Its spectrum between 0.4 and 2.5 µm suggests that it is most closely related to the Q taxonomic type of asteroid. The spectrum also closely matches that of the ordinary chondrites, the most common type of terrestrial meteorite. The geometric albedo of Braille is unusually high (pv=0.34), which is also consistent with its placement within the rarer classes of stony asteroids, and which suggests it has a relatively fresh, unweathered surface, perhaps due to a recent collision
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