803 research outputs found
An Investigation of Digital Reference Interviews: A Dialogue Act Approach
The rapid increase of computer-mediated communications (CMCs) in various forms such as micro-blogging (e.g. Twitter), online chatting (e.g. digital reference) and community- based question-answering services (e.g. Yahoo! Answers) characterizes a recent trend in web technologies, often referred to as the social web. This trend highlights the importance of supporting linguistic interactions in people\u27s online information-seeking activities in daily life - something that the web search engines still lack because of the complexity of this hu- man behavior. The presented research consists of an investigation of the information-seeking behavior of digital reference services through analysis of discourse semantics, called dialogue acts, and experimentation of automatic identification of dialogue acts using machine-learning techniques. The data was an online chat reference transaction archive, provided by the Online Computing Library Center (OCLC). Findings of the discourse analysis include supporting evidence of some of the existing theories of the information-seeking behavior. They also suggest a new way of analyzing the progress of information-seeking interactions using dia- logue act analysis. The machine learning experimentation produced promising results and demonstrated the possibility of practical applications of the DA analysis for further research across disciplines
Symmetricity of the Protocols Related to Oblivious Transfer (Foundations of Theoretical Computer Science : For New Computational View)
Adsorptive Removal of Fluoride onto Different Waste Materials: Orange Juice Residue, Waste Seaweed, and Spent Cation-Exchange Resin
To effectively use waste materials in developing a sustainable society, adsorbents for removing trace or low concentrations of fluoride, which is difficult to be removed by conventional techniques, were prepared from three waste materials: orange juice residue, waste sea weed, and spent cation exchange resin. These adsorbents were loaded with tri- or tetravalent metal ions such as iron(III) and zirconium(IV), of which zirconium(IV) was found to be most suitable as the loaded metal ion. From the pH effect on adsorption, the adsorption mechanism was inferred, and adsorption and desorption was found to be controlled by changing pH values. The maximum adsorption capacities on zirconium(IV)-loaded orange juice residue, waste sea weed, and spent cation exchange resin were evaluated as 33.1, 18.1, and 37.6 mg/g, respectively, which were higher than those of most other adsorbents reported in literatures. They exhibited high selectivity for fluoride over other anionic species and high durability. Tests to remove trace concentrations of fluoride from actual waste plating solutions revealed that the concentration could be reduced below the acceptable level using small amounts of these adsorbents, i.e., it was reduced lower than 1.5 mg/dm3 (WHO standard) by adding 1 g of the adsorbents into 1 dm3 test solution
Characteristics of physicians, their migration patterns and distance: a longitudinal study in Hiroshima, Japan
Introduction: Although some characteristics of physicians are known to be associated with their recruitment in rural and remote areas, the factors that predict mobility of physicians, and in particular, their mobility to rural and distant areas are largely unknown.
Methods: Flows of all physicians (n=4268) among municipalities in Hiroshima Prefecture, Japan, between 2002 and 2008 were analysed. Physician data were obtained from the National Physician Census. Municipality-level population data derived from the National Basic Resident Register were merged with the physician data. Information on the road distances of two municipalities measured with a geographic information system (GIS) was added to the physician cohort.
Results: During the period of study, 24.8% of physicians crossed municipal borders, and among them, 66.6% moved distances of less than 60 min travel time. The number of migrated physicians decreased as the distance increased, which held true for both migration to urban and rural areas. In the univariate analysis, female, younger, and hospital physicians were more mobile to rural areas than were male, older, and clinic physicians. Male and younger (≤40 years) physicians moved a longer distance than female and older physicians. Multivariate analysis revealed that age was a negative predictor (odds ratio [OR] per 10 years 0.62, 95% confidence interval [CI] 0.55-0.70]), and affiliation with a hospital was a positive predictor of migration to rural areas (OR 6.19 [95% CI 4.21-9.10]). Male sex (OR 1.67 [95% CI 1.11-2.50]) and hospital affiliation (OR 5.61 [95% CI 3.33-9.45]) were positive predictors, and age (OR per 10 years 0.39 [95% CI 0.33-0.46]) was a negative predictor of migrating a long distance.
Conclusion: In order to attract physicians to rural and remote areas, health workforce policies need to set a target population of physicians who are highly mobile to such places. Combining known predictors of rural practice, such as physicians with rural background and primary care physicians, and the mobility predictors shown in this study (ie young, hospital and male physicians) would make the target more appropriate and policies more effective.The Ministry of Education, Culture, Sports, Science and Technology (Tokyo, Japan) and Satake Education and Research Fund (Hiroshima, Japan) sponsored this research
Captan-induced increase in the concentrations of intracellular Ca2+ and Zn2+ and its correlation with oxidative stress in rat thymic lymphocytes
Captan, a phthalimide fungicide, is considered to be relatively nontoxic to mammals. There is a possibility that captan affects membrane and cellular parameters of mammalian cells, resulting in adverse effects, because of high residue levels. To test the possibility, we examined the effects of captan on rat thymic lymphocytes using flow-cytometry with appropriate fluorescent probes. Treatment with 10 and 30 μM captan induced apoptotic and necrotic cell death. Before cell death occurred, captan elevated the intracellular concentrations of Ca2+ and Zn2+ and decreased the concentration of cellular thiol compounds. These captan-induced phenomena are shown to cause cell death and are similar to those caused by oxidative stress. Captan also elevated the cytotoxicity of hydrogen peroxide. Results indicate that 10 and 30 μM captan cause cytotoxic effects on mammalian cells. Despite no report on the significant environmental toxicity hazard of captan in humans, it may exhibit adverse effects, described above, on wild organisms
Distributed probability of slope failure in Thailand under climate change
Landslides are more widespread compared to any other geological hazards in Thailand. The steep slope and high elevation areas have more potential for landslide hazards. However, weather extremes, particularly extreme rainfall, play a major role in the occurrence of landslides in Thailand. The objective of the present study is to analyze the changes in the probability of landslide occurrences in Thailand due to climate change. For this purpose, probabilistic landslide hazard maps for extreme rainfall values for 5-, 10-, 50-, and 100-year return periods are developed for historical and future climatic conditions, derived from 10 global climate models (GCMs) under two representative concentration pathway (RCP) scenarios, namely, RCP 4.5 and RCP 8.5. The results reveal that the 5-year return period extreme rainfall amount will reach 200 mm/month in the eastern and southern provinces for RCP 4.5 and the northwestern, eastern, and southern provinces for RCP 8.5. The increase in extreme rainfall will cause a sharp increase in the landslide probability in Thailand, except in low altitude regions. The probability of 100-year return period landslide will increase by 90% in 40% and 80% of the areas in Thailand under RCP 4.5 and RCP 8.5, respectively. It is expected that the landslide hazard maps developed in this study will help policy makers take necessary measures to mitigate increasing landslide events due to climate change. Keywords: Climate scenarios, Extreme rainfall, Global circulation models, Landslide, Thailan
ウサギ脊髄虚血モデルにおけるミノサイクリンの神経保護作用の評価
OBJECTIVE: To investigate whether postischemic administration of minocycline attenuates hind-limb motor dysfunction and gray and white matter injuries after spinal cord ischemia.
DESIGN: A prospective, randomized, laboratory investigation.
SETTING: Laboratory in university, single institution.
PARTICIPANTS: Male New Zealand White rabbits.
INTERVENTION: Spinal cord ischemia was induced by an occlusion of the infrarenal aorta for 15 minutes. The groups were administered minocycline 1 hour after reperfusion (M-1; n = 8), minocycline 3 hours after reperfusion (M-3; n = 8), saline 1 hour after reperfusion (control [C]; n = 8), or saline and no occlusion (sham; n = 4). Minocycline was administered intravenously at 10 mg/kg 6 times at 12-hour intervals until 60 hours after the initial administration.
MEASUREMENT AND MAIN RESULTS: Hind-limb motor function was assessed using the Tarlov score. For histologic assessments, gray and white matter injuries were evaluated 72 hours after reperfusion using the number of normal neurons and the percentage of areas of vacuolation, respectively. Motor function 72 hours after reperfusion was significantly better in group M-1 than in group C. The number of neurons in the anterior horn was significantly larger in group M-1 than in groups M-3 or C but did not differ significantly between groups M-3 and C. No significant difference was noted in the percentage of areas of vacuolation among the ischemia groups.
CONCLUSIONS: Minocycline administration beginning at 1 hour after reperfusion improved hind-limb motor dysfunction and attenuated gray matter injury in a rabbit spinal cord ischemia model.博士(医学)・乙第1314号・平成25年5月29
Scanning Tunneling Microscopy Measurements of the Local Work Function around Steps on the Au/Cu(111) Surface(STM-local states)
With a scanning tunneling microscope we have taken local work function images of the Au/Cu(111) surface. The local work function measured from large Au-covered terraces is in good agreement with the result obtained by non-local techniques, and the local work function around step edges is significantly lower than that on terraces. The experimental details of the local work function lowering around a step can be reproduced nicely with a simple simulation if a dipole moment row with a proper linear density is put at the center of the step and if the influence of the topographic change of the step due to formation of the dipole moment is taken into account. It is demonstrated that STM has the ability to reveal the details of how local work function varies around steps and other defects on metal surfaces
- …