267 research outputs found
Culture shapes how we look at faces
Background: Face processing, amongst many basic visual skills, is thought to be invariant across all humans. From as early as 1965, studies of eye movements have consistently revealed a systematic triangular sequence of fixations over the eyes and the mouth, suggesting that faces elicit a universal, biologically-determined information extraction pattern. Methodology/Principal Findings: Here we monitored the eye movements of Western Caucasian and East Asian observers while they learned, recognized, and categorized by race Western Caucasian and East Asian faces. Western Caucasian observers reproduced a scattered triangular pattern of fixations for faces of both races and across tasks. Contrary to intuition, East Asian observers focused more on the central region of the face. Conclusions/Significance: These results demonstrate that face processing can no longer be considered as arising from a universal series of perceptual events. The strategy employed to extract visual information from faces differs across cultures
Deuteron life-time in hot and dense nuclear matter near equilibrium
We consider deuteron formation in hot and dense nuclear matter close to
equilibrium and evaluate the life-time of the deuteron fluctuations within the
linear response theory. To this end we derive a generalized linear Boltzmann
equation where the collision integral is related to equilibrium correlation
functions. In this framework we then utilize finite temperature Green functions
to evaluate the collision integrals. The elementary reaction cross section is
evaluated within the Faddeev approach that is suitably modified to reflect the
properties of the surrounding hot and dense matter.Comment: 15 pages, 5 figure
Infinite square-well, trigonometric P\"oschl-Teller and other potential wells with a moving barrier
Using mainly two techniques, a point transformation and a time dependent
supersymmetry, we construct in sequence several quantum infinite potential
wells with a moving barrier. We depart from the well known system of a
one-dimensional particle in a box. With a point transformation, an infinite
square-well potential with a moving barrier is generated. Using time dependent
supersymmetry, the latter leads to a trigonometric P\"oschl-Teller potential
with a moving barrier. Finally, a confluent time dependent supersymmetry
transformation is implemented to generate new infinite potential wells, all of
them with a moving barrier. For all systems, solutions of the corresponding
time dependent Schr\"odinger equation fulfilling boundary conditions are
presented in a closed form
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Letter processing and font information during reading: beyond distinctiveness, where vision meets design
Letter identification is a critical front end of the
reading process. In general, conceptualizations of the identification process have emphasized arbitrary sets of distinctive features. However, a richer view of letter processing incorporates principles from the field of type design, including an emphasis on uniformities across letters within a font. The importance of uniformities is supported by a small body of research indicating that consistency of font increases letter identification efficiency. We review design concepts and the relevant literature, with the goal of stimulating further thinking about letter processing during reading
Elucidation of the mode of interaction in the UP1–telomerase RNA–telomeric DNA ternary complex which serves to recruit telomerase to telomeric DNA and to enhance the telomerase activity
We found that UP1, a proteolytic product of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), both enhances and represses the telomerase activity. The formation of the UP1–telomerase RNA–telomeric DNA ternary complex was revealed by a gel retardation experiment. The interactions in the ternary and binary complexes were elucidated by NMR. UP1 has two nucleic acid-binding domains, BD1 and BD2. In the UP1–telomerase RNA binary complex, both BD1 and BD2 interact with telomerase RNA. Interestingly, when telomeric DNA was added to the binary complex, telomeric DNA bound to BD1 in place of telomerase RNA. Thus, BD1 basically binds to telomeric DNA, while BD2 mainly binds to telomerase RNA, which resulted in the formation of the ternary complex. Here, UP1 bridges telomerase and telomeric DNA. It is supposed that UP1/hnRNP A1 serves to recruit telomerase to telomeric DNA through the formation of the ternary complex. A model has been proposed for how hnRNP A1/UP1 contributes to enhancement of the telomerase activity through recruitment and unfolding of the quadruplex of telomeric DNA
Enhancing treatment decision-making: pilot study of a treatment decision aid in stage IV non-small cell lung cancer
We developed a decision aid (DA) for patients with metastatic non-small cell lung cancer (NSCLC), to better inform patients of their prognosis and treatment options, and facilitate involvement in decision-making. In a pilot study, 20 patients with metastatic NSCLC attending outpatient clinics at a major cancer centre, who had already made a treatment decision, reviewed acceptability of the DA. The median age of the patients was 61 years (range 37–77 years), 35% were male, 20% had a university education, and most (75%) had English as a first language. Most had received chemotherapy, with 65% currently on treatment. Patients were not anxious at baseline and had clear understanding of the goals and toxicity of chemotherapy in advanced NSCLC. After reviewing the DA, patients' anxiety decreased slightly (P=0.04) and knowledge scores improved by 25% (P<0.001). Most improvements in understanding were of prognosis with and without chemotherapy, although patients still believed advanced NSCLC to be curable. Patients rated the DA highly with respect to information clarity, usefulness and were positive about its use in practice, although 40% found the prognostic information slightly upsetting. The DA for advanced NSCLC is feasible, acceptable to patients and improves understanding of advanced NSCLC without increasing patient anxiety
Canada’s Contributions to the SWOT Mission–Terrestrial Hydrology(SWOT-C TH)
The origins of the Surface Water and Ocean Topography (SWOT) mission date back to the mid-1970s with the launch of GOES-3 and SEASAT. These missions were then followed in 1992 by the Topex-Poseidon satellite, then by Jason-1 (2001), OSTM/Jason-2 (2008), and Jason 3 (2016), a series of joint satellite missions between NASA and CNES with a goal to monitor global ocean circulation. The proposed new SWOT mission will provide 120-km-wide swath interferometric coverage with a 20-km-wide gap at the nadir. The SWOT measurements will consist of water surface elevations and water surface slopes covering nearly all of the earth’s land surface at least once every 21 days. In 2010, NASA invited the Canadian Space Agency to contribute, and Canadian scientists welcomed the invitation to join the SWOT Science Definition Team and contribute to the experiments. The Canadian segment of the mission is known as the “SWOT-C” project. The SWOT satellite mission will provide unique opportunities in the Canadian context for water managers in both the public domain and in the private sector. This paper provides an overview of recent scientific progress by the SWOT-C Terrestrial Hydrology team, outlining current plans and progress towards applications and calibration post-launch
Deferred imitation and declarative memory in domestic dogs
This study demonstrates for the first time deferred imitation of novel actions in dogs (Canis familiaris) with retention intervals of 1.5 min and memory of familiar actions with intervals ranging from 0.40 to 10 min. Eight dogs were trained using the 'Do as I do' method to match their own behaviour to actions displayed by a human demonstrator. They were then trained to wait for a short interval to elapse before they were allowed to show the previously demonstrated action. The dogs were then tested for memory of the demonstrated behaviour in various conditions, also with the so-called two-action procedure and in a control condition without demonstration. Dogs were typically able to reproduce familiar actions after intervals as long as 10 min, even if distracted by different activities during the retention interval and were able to match their behaviour to the demonstration of a novel action after a delay of 1 min. In the two-action procedure, dogs were typically able to imitate the novel demonstrated behaviour after retention intervals of 1.5 min. The ability to encode and recall an action after a delay implies that facilitative processes cannot exhaustively explain the observed behavioural similarity and that dogs' imitative abilities are rather based on an enduring mental representation of the demonstration. Furthermore, the ability to imitate a novel action after a delay without previous practice suggests presence of declarative memory in dogs. © 2013 Springer-Verlag Berlin Heidelberg
Fetching what the owner prefers? Dogs recognize disgust and happiness in human behaviour
Comparing dogs and great apes in their ability to visually track object transpositions
Knowing that objects continue to exist after disappearing from sight and tracking invisible object displacements are two basic elements of spatial cognition. The current study compares dogs and apes in an invisible transposition task. Food was hidden under one of two cups in full view of the subject. After that both cups were displaced, systematically varying two main factors, whether cups were crossed during displacement and whether the cups were substituted by the other cup or instead cups were moved to new locations. While the apes were successful in all conditions, the dogs had a strong preference to approach the location where they last saw the reward, especially if this location remained filled. In addition, dogs seem to have especial difficulties to track the reward when both containers crossed their path during displacement. These results confirm the substantial difference that exists between great apes and dogs with regard to mental representation abilities required to track the invisible displacements of objects
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