337 research outputs found

    Clique: Perceptually Based, Task Oriented Auditory Display for GUI Applications

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    Screen reading is the prevalent approach for presenting graphical desktop applications in audio. The primary function of a screen reader is to describe what the user encounters when interacting with a graphical user interface (GUI). This straightforward method allows people with visual impairments to hear exactly what is on the screen, but with significant usability problems in a multitasking environment. Screen reader users must infer the state of on-going tasks spanning multiple graphical windows from a single, serial stream of speech. In this dissertation, I explore a new approach to enabling auditory display of GUI programs. With this method, the display describes concurrent application tasks using a small set of simultaneous speech and sound streams. The user listens to and interacts solely with this display, never with the underlying graphical interfaces. Scripts support this level of adaption by mapping GUI components to task definitions. Evaluation of this approach shows improvements in user efficiency, satisfaction, and understanding with little development effort. To develop this method, I studied the literature on existing auditory displays, working user behavior, and theories of human auditory perception and processing. I then conducted a user study to observe problems encountered and techniques employed by users interacting with an ideal auditory display: another human being. Based on my findings, I designed and implemented a prototype auditory display, called Clique, along with scripts adapting seven GUI applications. I concluded my work by conducting a variety of evaluations on Clique. The results of these studies show the following benefits of Clique over the state of the art for users with visual impairments (1-5) and mobile sighted users (6): 1. Faster, accurate access to speech utterances through concurrent speech streams. 2. Better awareness of peripheral information via concurrent speech and sound streams. 3. Increased information bandwidth through concurrent streams. 4. More efficient information seeking enabled by ubiquitous tools for browsing and searching. 5. Greater accuracy in describing unfamiliar applications learned using a consistent, task-based user interface. 6. Faster completion of email tasks in a standard GUI after exposure to those tasks in audio

    The Acute and Early Effects of Whole-Brain Irradiation on Glial Activation, Brain Metabolism, and Behavior:a Positron Emission Tomography Study

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    Purpose: Radiotherapy is a frequently applied treatment modality for brain tumors. Concomitant irradiation of normal brain tissue can induce various physiological responses. The aim of this study was to investigate whether acute and early-delayed effects of brain irradiation on glial activation and brain metabolism can be detected with positron emission tomography (PET) and whether these effects are correlated with behavioral changes. Procedures: Rats underwent 0-, 10-, or 25-Gy whole-brain irradiation. At 3 and 31 days post irradiation, 1-(2-chlorophenyl)-N-[11C]methyl-(1-methylpropyl)-3-isoquinoline carboxamide ([11C]PK11195) and 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) PET scans were acquired to detect changes in glial activation (neuroinflammation) and glucose metabolism, respectively. The open-field test (OFT) was performed on days 6 and 27 to assess behavioral changes. Results: Twenty-five-gray-irradiated rats showed higher [11C]PK11195 uptake in most brain regions than controls on day 3 (striatum, hypothalamus, accumbens, septum p < 0.05), although some brain regions had lower uptake (cerebellum, parietal association/retrosplenial visual cortex, frontal association/motor cortex, somatosensory cortex, p < 0.05). On day 31, several brain regions in 25-Gy-irradiated rats still showed significantly higher [11C]PK11195 uptake than controls and 10-Gy-irradiated group (p < 0.05). Within-group analysis showed that [11C]PK11195 uptake in individual brain regions of 25-Gy treated rats remained stable or slightly increased between days 3 and 31. In contrast, a significant reduction (p < 0.05) in tracer uptake between days 3 and 31 was found in all brain areas of controls and 10-Gy-irradiated animals. Moreover, 10-Gy treatment led to a significantly higher [18F]FDG uptake on day 3 (p < 0.05). [18F]FDG uptake decreased between days 3 and 31 in all groups; no significant differences between groups were observed anymore on day 31, except for increased uptake in the hypothalamus in the 10-Gy group. The OFT did not show any significant differences between groups. Conclusions: Non-invasive PET imaging indicated that brain irradiation induces neuroinflammation and a metabolic flare, without causing acute or early-delayed behavioral changes

    Interactive audio-tactile maps for visually impaired people

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    International audienceVisually impaired people face important challenges related to orientation and mobility. Indeed, 56% of visually impaired people in France declared having problems concerning autonomous mobility. These problems often mean that visually impaired people travel less, which influences their personal and professional life and can lead to exclusion from society. Therefore this issue presents a social challenge as well as an important research area. Accessible geographic maps are helpful for acquiring knowledge about a city's or neighborhood's configuration, as well as selecting a route to reach a destination. Traditionally, raised-line paper maps with braille text have been used. These maps have proved to be efficient for the acquisition of spatial knowledge by visually impaired people. Yet, these maps possess significant limitations. For instance, due to the specificities of the tactile sense only a limited amount of information can be displayed on a single map, which dramatically increases the number of maps that are needed. For the same reason, it is difficult to represent specific information such as distances. Finally, braille labels are used for textual descriptions but only a small percentage of the visually impaired population reads braille. In France 15% of blind people are braille readers and only 10% can read and write. In the United States, fewer than 10% of the legally blind people are braille readers and only 10% of blind children actually learn braille. Recent technological advances have enabled the design of interactive maps with the aim to overcome these limitations. Indeed, interactive maps have the potential to provide a broad spectrum of the population with spatial knowledge, irrespective of age, impairment, skill level, or other factors. To this regard, they might be an efficient means for providing visually impaired people with access to geospatial information. In this paper we give an overview of our research on making geographic maps accessible to visually impaired people

    Construção e Avaliação para 15 Listas de Palavras Baseadas no Paradigma Deese-Roediger-McDermott

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    Based on studies conducted in accordance with the Deese-Roediger-McDermott (DRM) paradigm, in which words of a list tend to evoke other related items, used in false memory research, this study produced 15 lists of semantically related words for Brazilian Portuguese. For the preparation of the lists, certain criteria were considered, such as word length and frequency of words in a Brazilian Portuguese corpus. Pre-selection guided by linguistic characteristics aimed to control possible biases among volunteers. Semantic association and concreteness tests were carried out to determine the suitability of the selected items, and a free recall test was performed to evaluate evocation characteristics. We suggest using word lists in researches that evaluate false memories.Com base nos estudos conduzidos de acordo com o paradigma Deese-Roediger-McDermott (DRM), em quais palavras de uma lista tendem a evocar outros itens relacionados, utilizado em pesquisas de falsas memórias, neste estudo elaborou-se 15 listas de palavras semanticamente relacionadas para o português. Para a elaboração das listas, foram considerados critérios como frequência de palavras no corpus de português brasileiro e extensão de palavras. A pré-seleção guiada por características linguísticas visava controlar possíveis vieses por parte dos voluntários. Testes de associação semântica e concretude de palavras foram realizados para apurar a conveniência dos itens selecionados, e um teste de recordação livre foi conduzido para avaliar características de evocação. Sugerimos a utilização das listas de palavras em pesquisas que avaliem falsas memórias

    QED self-energy contribution to highly-excited atomic states

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    We present numerical values for the self-energy shifts predicted by QED (Quantum Electrodynamics) for hydrogenlike ions (nuclear charge 60Z11060 \le Z \le 110) with an electron in an n=3n=3, 4 or 5 level with high angular momentum (5/2j9/25/2\le j \le 9/2). Applications include predictions of precision transition energies and studies of the outer-shell structure of atoms and ions.Comment: 20 pages, 5 figure

    Morphological Deformities as Biomarkers in Fish from Contaminated Rivers in Taiwan

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    Tilapia (Oreochromis spp.) were collected seasonally from four contaminated rivers in southwestern Taiwan for studies of morphological deformities that could be used as biomarkers of contamination. Morphological deformities found in tilapia were separated into 15 categories. Overall, the prevalence of deformities such as split fins, lower lip extension and gill deformities were significantly related to various water quality parameters, including low DO and high ammonium, lead and zinc concentrations. The persistence of tilapia in polluted waters and the development of a suite of morphological deformities suggest that tilapia can be used as sentinels of non-point source pollution in rivers

    Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

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    A measurement of the cosmic-ray spectrum for energies exceeding 4×10184{\times}10^{18} eV is presented, which is based on the analysis of showers with zenith angles greater than 6060^{\circ} detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10185.3{\times}10^{18} eV, the "ankle", the flux can be described by a power law EγE^{-\gamma} with index γ=2.70±0.02(stat)±0.1(sys)\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)} followed by a smooth suppression region. For the energy (EsE_\text{s}) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25(stat)1.2+1.0(sys))×1019E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19} eV.Comment: Replaced with published version. Added journal reference and DO

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

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    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file
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