265 research outputs found

    Contextual queries and situated information needs for mobile users

    Get PDF
    The users of mobile devices increasingly use networked services to address their information needs. Questions asked by mobile users are strongly influenced by contextual factors such as location, conversation and activity. We report on a diary study performed to better understand mobile information needs. Participants’ diary entries are used as a basis for discussing the geographical and situational context in which mobile information behaviour occurs. The suitability of user queries to be answered by a portable knowledge collection and web search are also considered. We find that the type of questions recorded by participants varies across their locations, with differences between home, shopping and in-car contexts. These variations occur both in the query terms and in the form of desired answers. Both the location of queries and the participants’ activities affected participants’ questions. When information needs were affected by both location and activity, they tended to be strongly affected by both factors. The overall picture that emerges is one of multiple contextual influences interacting to shape mobile information needs. Mobile devices that attempt to adapt to users’ context will need to account for a rich variety of situational factors

    Contextual queries express mobile information needs

    Get PDF
    The users of mobile devices increasingly use networked services to address their information needs. Questions asked by mobile users are strongly influenced by contextual factors such as location, conversation and activity. We report on a diary study performed to better understand mobile information needs. We find that the type of questions recorded by participants varies across their locations, with differences between home, shopping and in-car contexts. These variations occur both in the query terms and in the form of desired answers. Both the location of queries and the participants' activities affected participants' questions. When information needs were affected by both location and activity, they tended to be strongly affected by both factors. The overall picture that emerges is one of multiple contextual influences interacting to shape mobile information needs. Mobile devices that attempt to adapt to users' context will need to account for a rich variety of situational factors

    Designing a mobile augmented memory system for people with traumatic brain injuries

    Get PDF
    Augmented memory systems help people remember events in their lives. Individuals with Traumatic Brain Injury (TBI) often have memory impairments. We conducted a user study to learn about strategies individuals with TBI use to remember events in their lives. We explored what characteristics individuals with TBI expect of an augmented memory system. We then investigated these aspects in an initial mobile app design, and propose here a concept for a rehearsal application that addresses the issues found in our studies

    Questions And Answers: Exploring Mobile User Needs

    Get PDF
    The users of mobile devices increasingly use networked services to address their information needs. Questions asked by mobile users are strongly influenced by context factors, such as location and user activity. However in research which has empirically documented the link between mobile information needs and context factors, information about expected answers is scant. Therefore, the goal of this study is to explore the context factors which influence the mobile information needs and the answers expected by mobile users. The results, are obtained by analysing information from paper diaries and digital diaries. This project involved a user study, comprising two different types of studies concerning a paper diary and a digital diary. The analysis of both the paper diary and the digital diary was conducted through grounded theory and taxonomy of information needs. our results indicate a relationship between mobile information needs and context factors and expected answers. Our study explored this relationship between mobile information needs and context factors, and provides a better understanding of the expected answers related to mobile information needs

    A Mobile Augmented Memory Aid for people with Traumatic Brain Injury

    Get PDF
    Traumatic Brain Injury (TBI) occurs when an external mechanical force traumatically injures the brain. The 2010/2011 population-based study shows that the total incidence of TBI in New Zealand has increased to 790 per 100,000 population. Memory impairment is the most common symptom and affects most TBI survivors. Memory impairments resulting from TBI take many forms depending on the nature of the injury. Existing work to use technology to help with memory problems focuses predominantly on capturing all information digitally to enable ‘replaying’ of memories. Other software applications (like calendar that reminders) are designed to assist the average people tracking their schedules. Both are inadequate for supporting TBI survivors. The aim of this research is to build an augmented autobiographical memory system for a mobile device for supporting TBI survivors with their memory problems. I address the lack of information about TBI survivors’ use of digital aids through user studies and interviews. This research includes three studies. The first study is the interview user study, which aims to investigate TBI survivors’ use of their own memory aids/strategies to cope with difficulties caused by memory impairments. The results contribute to develop the conceptual design of the prototype. The second study is the interface user study, which aims to examine the usability of the conceptual design. Findings from this study provide the data and feedback for structuring the implementation of the MyMemory prototype on a mobile device. MyMemory is an augmented autobiographical memory aid specialized for TBI survivors with memory impairments. According to the results from the interface user study, we develop the implementation of the MyMemory prototype. The third study aims to evaluate the effectiveness of MyMemory for improving autobiographical memory for people with TBI. This evaluation study is based on the ABAB case study used in psychology which can provide more accurate outcomes about the evaluation of MyMemory

    The Human Metapneumovirus Small Hydrophobic Protein has Properties Consistent with Those of a Viroporin and Can Modulate Viral Fusogenic Activity

    Get PDF
    Human metapneumovirus (HMPV) encodes three glycoproteins: the glycoprotein, which plays a role in glycosaminoglycan binding, the fusion (F) protein, which is necessary and sufficient for both viral binding to the target cell and fusion between the cellular plasma membrane and the viral membrane, and the small hydrophobic (SH) protein, whose function is unclear. The SH protein of the closely related respiratory syncytial virus has been suggested to function as a viroporin, as it forms oligomeric structures consistent with a pore and alters membrane permeability. Our analysis indicates that both the full-length HMPV SH protein and the isolated SH protein transmembrane domain can associate into higher-order oligomers. In addition, HMPV SH expression resulted in increases in permeability to hygromycin B and alteration of subcellular localization of a fluorescent dye, indicating that SH affects membrane permeability. These results suggest that the HMPV SH protein has several characteristics consistent with a putative viroporin. Interestingly, we also report that expression of the HMPV SH protein can significantly decrease HMPV F protein-promoted membrane fusion activity, with the SH extracellular domain and transmembrane domain playing a key role in this inhibition. These results suggest that the HMPV SH protein could regulate both membrane permeability and fusion protein function during viral infection. IMPORTANCE: Human metapneumovirus (HMPV), first identified in 2001, is a causative agent of severe respiratory tract disease worldwide. The small hydrophobic (SH) protein is one of three glycoproteins encoded by all strains of HMPV, but the function of the HMPV SH protein is unknown. We have determined that the HMPV SH protein can alter the permeability of cellular membranes, suggesting that HMPV SH is a member of a class of proteins termed viroporins, which modulate membrane permeability to facilitate critical steps in a viral life cycle. We also demonstrated that HMPV SH can inhibit the membrane fusion function of the HMPV fusion protein. This work suggests that the HMPV SH protein has several functions, though the steps in the HMPV life cycle impacted by these functions remain to be clarified

    Transforming Growth Factor β Blocks Tec Kinase Phosphorylation, Ca2+ Influx, and NFATc Translocation Causing Inhibition of T Cell Differentiation

    Get PDF
    Transforming growth factor (TGF)-β inhibits T cell proliferation and differentiation. TGF-β has been shown to inhibit the expression of transcription factors such as GATA-3 and T-bet that play important roles in T cell differentiation. Here we show that TGF-β inhibits T cell differentiation at a more proximal step. An early event during T cell activation is increased intracellular calcium levels. Calcium influx in activated T cells and the subsequent activation of transcription factors such as NFATc, events essential for T cell differentiation, are modulated by the Tec kinases that are downstream of the T cell receptor and CD28. We show that in stimulated CD4+ T cells, TGF-β inhibits phosphorylation and activation of the Tec kinase Itk, increase in intracellular Ca2+ levels, NFATc translocation, and activation of the mitogen-activated protein kinase ERK that together regulate T cell differentiation. Our studies suggest that by inhibiting Itk, and consequently Ca2+ influx, TGF-β limits T cell differentiation along both the Th1 and Th2 lineages

    Effect of chemical preservatives on shelf life of mushroom (Pleurotus ostreatus) cultivated on cassava peels

    Get PDF
    Short shelf life is a major impediment to the processing and distribution of mushroom. The effect of chemical preservatives on some quality attributes of mushroom during storage was investigated. Mushroom were soaked in four preservatives at two concentrations for 10 mins, packaged, stored at 4 °C for 30 days and analysed at intervals for their microbial population, colour, firmness and weight loss. Sodium benzoate (0.05%, 0.1%) lost its preservative effect on all the micro-organisms enumerated after 3 days, and samples treated with 0.1% potassium sorbate had the lowest microbial load at the end of the storage period. Change in colour of the potassium sorbate (0.1%)-treated sample was lower than and significantly different from the citric acid (2%, 4%)-treated samples. The values of the firmness of the 4% citric acid preserved mushroom were significantly different (P ≤ 0.05) from other samples throughout the storage period. There was a significant negative correlation (r = −0.807, P < 0.01) between the firmness and weight loss of the preserved mushroom. Potassium sorbate (0.1%) and citric acid (4%) extended the shelf life of mushroom for 24 days

    Feedhorn-coupled TES polarimeter camera modules at 150 GHz for CMB polarization measurements with SPTpol

    Full text link
    The SPTpol camera is a dichroic polarimetric receiver at 90 and 150 GHz. Deployed in January 2012 on the South Pole Telescope (SPT), SPTpol is looking for faint polarization signals in the Cosmic Microwave Background (CMB). The camera consists of 180 individual Transition Edge Sensor (TES) polarimeters at 90 GHz and seven 84-polarimeter camera modules (a total of 588 polarimeters) at 150 GHz. We present the design, dark characterization, and in-lab optical properties of the 150 GHz camera modules. The modules consist of photolithographed arrays of TES polarimeters coupled to silicon platelet arrays of corrugated feedhorns, both of which are fabricated at NIST-Boulder. In addition to mounting hardware and RF shielding, each module also contains a set of passive readout electronics for digital frequency-domain multiplexing. A single module, therefore, is fully functional as a miniature focal plane and can be tested independently. Across the modules tested before deployment, the detectors average a critical temperature of 478 mK, normal resistance R_N of 1.2 Ohm, unloaded saturation power of 22.5 pW, (detector-only) optical efficiency of ~ 90%, and have electrothermal time constants < 1 ms in transition.Comment: 15 pages, 11 figure
    corecore