325 research outputs found

    Repurposing Visual Input Modalities for Blind Users: A Case Study of Word Processors

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    Visual \u27point-and-click\u27 interaction artifacts such as mouse and touchpad are tangible input modalities, which are essential for sighted users to conveniently interact with computer applications. In contrast, blind users are unable to leverage these visual input modalities and are thus limited while interacting with computers using a sequentially narrating screen-reader assistive technology that is coupled to keyboards. As a consequence, blind users generally require significantly more time and effort to do even simple application tasks (e.g., applying a style to text in a word processor) using only keyboard, compared to their sighted peers who can effortlessly accomplish the same tasks using a point-and-click mouse. This paper explores the idea of repurposing visual input modalities for non-visual interaction so that blind users too can draw the benefits of simple and efficient access from these modalities. Specifically, with word processing applications as the representative case study, we designed and developed NVMouse as a concrete manifestation of this repurposing idea, in which the spatially distributed word-processor controls are mapped to a virtual hierarchical \u27Feature Menu\u27 that is easily traversable non-visually using simple scroll and click input actions. Furthermore, NVMouse enhances the efficiency of accessing frequently-used application commands by leveraging a data-driven prediction model that can determine what commands the user will most likely access next, given the current \u27local\u27 screen-reader context in the document. A user study with 14 blind participants comparing keyboard-based screen readers with NVMouse, showed that the latter significantly reduced both the task-completion times and user effort (i.e., number of user actions) for different word-processing activities

    Enabling Customization of Discussion Forums for Blind Users

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    Online discussion forums have become an integral component of news, entertainment, information, and video-streaming websites, where people all over the world actively engage in discussions on a wide range of topics including politics, sports, music, business, health, and world affairs. Yet, little is known about their usability for blind users, who aurally interact with the forum conversations using screen reader assistive technology. In an interview study, blind users stated that they often had an arduous and frustrating interaction experience while consuming conversation threads, mainly due to the highly redundant content and the absence of customization options to selectively view portions of the conversations. As an initial step towards addressing these usability concerns, we designed PView - a browser extension that enables blind users to customize the content of forum threads in real time as they interact with these threads. Specifically, PView allows the blind users to explicitly hide any post that is irrelevant to them, and then PView automatically detects and filters out all subsequent posts that are substantially similar to the hidden post in real time, before the users navigate to those portions of the thread. In a user study with blind participants, we observed that compared to the status quo, PView significantly improved the usability, workload, and satisfaction of the participants while interacting with the forums

    AutoDesc: Facilitating Convenient Perusal of Web Data Items for Blind Users

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    Web data items such as shopping products, classifieds, and job listings are indispensable components of most e-commerce websites. The information on the data items are typically distributed over two or more webpages, e.g., a ‘Query-Results’ page showing the summaries of the items, and ‘Details’ pages containing full information about the items. While this organization of data mitigates information overload and visual cluttering for sighted users, it however increases the interaction overhead and effort for blind users, as back-and-forth navigation between webpages using screen reader assistive technology is tedious and cumbersome. Existing usability-enhancing solutions are unable to provide adequate support in this regard as they predominantly focus on enabling efficient content access within a single webpage, and as such are not tailored for content distributed across multiple webpages. As an initial step towards addressing this issue, we developed AutoDesc, a browser extension that leverages a custom extraction model to automatically detect and pull out additional item descriptions from the ‘details’ pages, and then proactively inject the extracted information into the ‘Query-Results’ page, thereby reducing the amount of back-and-forth screen reader navigation between the two webpages. In a study with 16 blind users, we observed that within the same time duration, the participants were able to peruse significantly more data items on average with AutoDesc, compared to that with their preferred screen readers as well as with a state-of-the-art solution

    Intramedullary Clear Cell Ependymoma in the Thoracic Spinal Cord: A Case with Its Crush Smear and Ultrastructural Findings

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    Clear cell ependymoma was included in the World Health Organization classification of the nervous system in 1993, and all the reported cases, except for two in the spinal cord, were located in the brain, mainly in the supratentorial compartment. Astrocytomas outnumber ependymomas in the spinal cord, and the two entities partly share cytologic findings such as long, bipolar glial processes and oval to round nuclei resembling those seen in pilocytic astrocytoma. Here, we report the first Korean case of intramedullary clear cell ependymoma of the spinal cord, which is the third case situated in the spinal cord in the literature. The crush smear revealed round-to-oval nuclei with occasional nuclear eosinophilic inclusion and rare nuclear grooves. Cytoplasm had fluffy eosinophilic glial processes, and acellular fibrillary zone. On hematoxylin-eosin stain, oval to round tumor cells had large central nuclei with indistinct nucleoli and a moderate amount of clear cytoplasm, i.e. perinuclear halo, mimicking oligodendroglioma. Perivascular pseudorosettes and ependymal clefts were rarely found. In retrospect, perinuclear halo was absent on crush smears. Ultrastructurally, they had extensive surface microvilli and edematous cytoplasm filled with abundant glial filaments and microlumens with or without microvilli. Intercellular long cell junctions of the zipper-like zonula adherens type were found

    Fibrinogen gamma-A chain precursor in CSF: a candidate biomarker for Alzheimer's disease

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    <p>Abstract</p> <p>Background</p> <p>Cerebrospinal fluid (CSF) may be valuable for exploring protein markers for the diagnosis of Alzheimer's disease (AD). The prospect of early detection and treatment, to slow progression, holds hope for aging populations with increased average lifespan. The aim of the present study was to investigate candidate CSF biological markers in patients with mild cognitive impairment (MCI) and AD and compare them with age-matched normal control subjects.</p> <p>Methods</p> <p>We applied proteomics approaches to analyze CSF samples derived from 27 patients with AD, 3 subjects with MCI and 30 controls. The AD group was subdivided into three groups by clinical severity according to clinical dementia rating (CDR), a well known clinical scale for dementia.</p> <p>Results</p> <p>We demonstrated an elevated level of fibrinogen gamma-A chain precursor protein in CSF from patients with mild cognitive impairment and AD compared to the age-matched normal subjects. Moreover, its expression was more prominent in the AD group than in the MCI and correlated with disease severity and progression. In contrast, fibrinogen gamma-A chain precursor protein was detected very low in the age-matched normal group.</p> <p>Conclusion</p> <p>These findings suggest that the CSF level of fibrinogen gamma-A chain precursor may be a candidate biomarker for AD.</p

    A study on nutrition knowledge and dietary behavior of elementary school children in Seoul

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    The purpose of this study was to investigate the nutrition and diet related knowledge, attitude, and behavior of elementary school children in Seoul. The subjects included were 439 (male 236, female 203) elementary school children in the 4th to the 6th grades. The statistical analysis was conducted using SPSS 12.0 program. The average obesity index (OI) was 104.98 and 99.82 for male and female subjects, respectively. The average percentage of underweight, normal, overweight and obese of subjects was 33.7%, 32.8%, 12.3%, and 19.4%, respectively. The percentage of the underweight group of female subjects was higher than that of the male subjects. The percentage of the obese group of male subjects was higher than that of the female subjects. The average score of nutrition knowledge, nutrition attitude and dietary behavior was 6.8, 7.44, and 7.34, respectively. Dietary behavior of male subjects was positively correlated with parents' education levels, monthly household income and nutrition attitude. Dietary behavior of female subjects was positively correlated with monthly household income, nutrition knowledge and nutrition attitude. Dietary behavior of female subjects was positively correlated with obesity index (OI). Proper nutrition education and intervention are required for the improvement of elementary school children's nutrition knowledge, nutrition attitudes and dietary behaviors

    Anti-apoptotic effects of human placental hydrolysate against hepatocyte toxicity in vivo and in vitro

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    Apoptosis and oxidative stress are essential for the pathogenesis of acute liver failure and fulminant hepatic failure. Human placental hydrolysate (hPH) has been reported to possess antioxidant and anti-inflammatory properties. In the present study, the protective effects of hPH against D-galactosamine (D-GalN)- and lipopolysaccharide (LPS)-induced hepatocyte apoptosis were investigated in vivo. In addition, the molecular mechanisms underlying the anti-apoptotic activities of hPH against D-GalN-induced cell death in vitro were examined. Male Sprague-D awley rats were injected with D-GaIN/LPS with or without the administration of hPH. Rats were sacrificed 24 h after D-GaIN/LPS intraperitoneal injection, and the blood and liver samples were collected for future inflammation and hepatotoxicity analyses. Changes in cell viability, apoptosis protein expression, mitochondrial mass, mitochondrial membrane potential, reactive oxygen species generation, and the levels of proteins and mRNA associated with a protective mechanism were determined in HepG2 cells pretreated with hPH for 2 h prior to D-GalN exposure. The findings suggested that hPH treatment effectively protected against D-GalN/LPS-induced hepatocyte apoptosis by reducing the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, interleukin-6, and tumor necrosis factor-α, and increasing the level of proliferating cell nuclear antigen. It was also found that hPH inhibited the apoptotic cell death induced by D-GalN. hPH activated the expression of antioxidant enzymes, including superoxide dismutase, glutathione peroxidase, and catalase, which were further upregulated by the Kelch-like ECH2-associated protein 1-p62-nuclear factor-erythroid 2-related factor 2 pathway, a component of oxidative stress defense mechanisms. Furthermore, hPH markedly reduced cytosolic and mitochondrial reactive oxygen species and rescued mitochondrial loss and dysfunction through the reduction of damage-regulated autophagy modulator, p53, and C/EBP homologous protein. Collectively, hPH exhibited a protective role in hepatocyte apoptosis by inhibiting oxidative stress and maintaining cell homeostasis. The underlying mechanisms may be associated with the inhibition of endoplasmic reticulum stress and minimization of the autophagy progress
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