830 research outputs found

    Toward an Evaluation Model of User Experiences on Virtual Reality Indoor Bikes

    Get PDF
    This paper deals with deriving a model or framework to evaluate user experiences (UX) of virtual reality (VR) systems, especially, VR indoor bikes which are under construction. Recently, VR is one of the most appealing areas attracting people’s interests around the world. Many products armed with it increasingly emerge on the market, and it is expected that the use of VR systems will continue to increase sharply in the future. However, UX of such products cannot be evaluated appropriately at the moment due to a lack of proper evaluation models. In a broad sense, UX that may stem from human machine interface in ergonomics covers affect, usability, and user value in spite of some differences in definition among the researchers. While evaluations of UX on the products without VR have been overall justifiably performed, UX has been evaluated neither systematically nor strictly on the products with VR. Through the analyses of expert reviews, we newly identify an additional component and its elements, and modify some elements of the three existing components for evaluating UX on the VR systems. As a result, we propose a comprehensive evaluation model of UX, which consists of four factors: usability, affect, user value, and presence feeling. In addition, we determine the components and their elements for specific VR indoor bikes similarly through the analyses of expert surveys and focus-group discussions, which results in developing a questionnaire for users. Finally, along with the questionnaire, we propose a specific evaluation model for VR indoor bikes

    Performances of serum creatinine, C-reactive protein and white blood cell to predict urinary tract infection in febrile children younger than 24 months of age

    Get PDF
    Purpose Differentiation of urinary tract infection (UTI) from viral infection is a critical challenge in febrile children in emergency departments (EDs). This study aimed to assess the predicting performances of creatinine, C-reactive protein (CRP), and white blood cell (WBC) for predicting UTI in the children. Methods This study was a retrospective analysis of a prospectively enrolled cohort of febrile children who presented to our children’s hospital ED from August 2016 through February 2018. We included previously healthy, febrile (≥ 38。C) children younger than 24 months whose urine cultures were obtained. Accuracy of creatinine, CRP, and WBC were assessed by optimal cutoffs, which were calculated using receiver operating characteristic curves. Results Among the total 33,013 children to the ED, 7,847 (23.8%) febrile children were registered to the fever registry. Finally, 506 children were included, and UTI was diagnosed in 127 (25.1%). The areas under the curve of creatinine, CRP, and WBC to predict UTI were 0.41 (95% confidence interval [CI], 0.35-0.46), 0.71 (95% CI, 0.66-0.77), and 0.66 (95% CI, 0.60-0.72), respectively. The cutoffs were 0.26 mg/dL for creatinine, 2.3 mg/dL for CRP, and 14.4 × 103 cells/μL for WBC. Creatinine showed worse performance than the other variables. The application of creatinine added to the other variables led to an increase only in the sensitivity, but at the expense of a lower specificity, positive predictive value, and negative predictive value. Conclusion Serum creatinine showed a poor performance in predicting UTI in the febrile young children. Since a single biomarker can neither rule in nor rule out UTI in the children, the prediction of UTI can be achieved by the interpretation of both clinical and laboratory findings

    Electrically Robust Single-Crystalline WTe2 Nanobelts for Nanoscale Electrical Interconnects

    Get PDF
    As the elements of integrated circuits are downsized to the nanoscale, the current Cu-based interconnects are facing limitations due to increased resistivity and decreased current-carrying capacity because of scaling. Here, the bottom-up synthesis of single-crystalline WTe2 nanobelts and low- and high-field electrical characterization of nanoscale interconnect test structures in various ambient conditions are reported. Unlike exfoliated flakes obtained by the top-down approach, the bottom-up growth mode of WTe2 nanobelts allows systemic characterization of the electrical properties of WTe2 single crystals as a function of channel dimensions. Using a 1D heat transport model and a power law, it is determined that the breakdown of WTe2 devices under vacuum and with AlOx capping layer follows an ideal pattern for Joule heating, far from edge scattering. High-field electrical measurements and self-heating modeling demonstrate that the WTe2 nanobelts have a breakdown current density approaching approximate to 100 MA cm(-2), remarkably higher than those of conventional metals and other transition-metal chalcogenides, and sustain the highest electrical power per channel length (approximate to 16.4 W cm(-1)) among the interconnect candidates. The results suggest superior robustness of WTe2 against high-bias sweep and its possible applicability in future nanoelectronics

    Theory of current-driven motion of Skyrmions and spirals in helical magnets

    Full text link
    We study theoretically the dynamics of the spin textures, i.e., Skyrmion crystal (SkX) and spiral structure (SS), in two-dimensional helical magnets under external current. By numerically solving the Landau-Lifshitz-Gilbert equation, it is found that (i) the critical current density of the motion is much lower for SkX compared with SS in agreement with the recent experiment, (ii) there is no intrinsic pinning effect for SkX and the deformation of the internal structure of Skyrmion reduces the pinning effect dramatically, (iii) the Bragg intensity of SkX shows strong time-dependence as can be observed by neutron scattering experiment.Comment: 4 pages, 3 figure

    Photobiocidal-triboelectric nanolayer coating of photosensitizer/silica-alumina for reusable and visible-light-driven antibacterial/antiviral air filters

    Get PDF
    Outbreaks of airborne pathogens pose a major threat to public health. Here we present a single-step nanocoating process to endow commercial face mask filters with photobiocidal activity, triboelectric filtration capability, and washability. These functions were successfully achieved with a composite nanolayer of silica-alumina (Si-Al) sol-gel, crystal violet (CV) photosensitizer, and hydrophobic electronegative molecules of 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (PFOTES). The transparent Si-Al matrix strongly immobilized the photosensitizer molecules while dispersing them spatially, thus suppressing self-quenching. During nanolayer formation, PFOTES was anisotropically rearranged on the Si-Al matrix, promoting moisture resistance and triboelectric charging of the Si-Al/PFOTES-CV (SAPC)-coated filter. The SAPC nanolayer stabilized the photoexcited state of the photosensitizer and promoted redox reaction. Compared to pure-photosensitizer-coated filters, the SAPC filter showed substantially higher photobiocidal efficiency (∼99.99 % for bacteria and a virus) and photodurability (∼83 % reduction in bactericidal efficiency for the pure-photosensitizer filter but ∼0.34 % for the SAPC filter after 72 h of light irradiation). Moreover, after five washes with detergent, the SAPC filter maintained its photobiocidal and filtration performance, proving its reusability potential. Therefore, this SAPC nanolayer coating provides a practical strategy for manufacturing an antimicrobial and reusable mask filter for use during the ongoing COVID-19 pandemic

    Epidemiologic features of pediatric genital injury in emergency departments in Korea

    Get PDF
    Purpose Genital injury is a common pediatric injury. Given the lack of nationwide data, the authors aimed to show age group-related epidemiologic features of genital injury in Korea. Methods We reviewed the data from 2011-2016 Emergency Department-based Injury In-depth Surveillance registry, which involves 23 emergency departments in Korea. From the dataset, we included children (< 18 years) with the International Classification of Diseases, 10th Revision codes related to genital injury as the final diagnosis with excluding those with other codes or combined injuries. Age groups were defined as follows; infants (< 1 year), toddlers (1-3), preschoolers (4-6), schoolers (7-12), and adolescents (13-17). The clinical features and outcomes were analyzed. Results A total of 3,030 children were included with the median age of 6 years (interquartile range, 4-10) and the proportion of girls of 53.0%. Only 144 children (4.8%) were transported by the emergency medical service providers. The most common mechanism and place were blunt injury (1,826 [60.3%]) and home (1,535 [50.7%]), respectively. Of the codes, “Contusion of external genital organs (S30.2)” was most common (1,574 [51.9%]). As for outcomes, 2,770 children (91.4%) were discharged, 252 (8.3%) were hospitalized (intensive care units, 1 child [0.03%]), and 108 (3.6%) underwent surgery. Severe injury occurred in 111 children (3.7%) without a mortality. With increasing age in the age groups, non-accidental injury, school and sports-related injuries, hospitalization, and surgery (All Ps < 0.001). Conclusion Genital injury may occur at evening, in spring and summer, at home, and in the form of accidental or blunt injury. Most children are discharged. Contrary to these general features, older children tend to undergo more frequently non-accidental injury, school and sports-related injuries, hospitalization, and surgery. Thus, we need age-specific strategies for injury prevention

    Protein deficiency balance as a predictor of clinical outcome in hereditary spherocytosis

    Get PDF
    Vertical and horizontal interactions between membrane constituents account for integrity, strength and deformability of the erythrocyte. Disruption of vertical interactions caused by membrane protein deficiencies in hereditary spherocytosis (HS), favor membrane vesiculation with development of spherocytic cells. Our aim was to evaluate the hematological and clinical presentation of HS according to the type and amount of protein deficiency. We studied 81 Portuguese individuals, 71 belonging to 21 families plus 10 unrelated subjects, and found that 51 of them were HS patients. Patients were classified as presenting mild, typical or severe HS, according to laboratory results and clinical follow-up. We performed screening tests and the standardized electrophoretic membrane protein analysis to identify and quantify protein deficiencies. We found band 3 and ankyrin deficiencies as the major causes for HS. The ratios between the value of the primary and/or secondary protein deficiencies showed significantly different values according to the severity of HS, and a significant inverse correlation with the severity of HS was observed. In mild HS, the ratios between protein deficiencies reflected equivalent protein deficiencies, while an unbalance was observed in typical HS, which was enhanced in severe HS. Our data suggest that the relative quantification of each major membrane protein and of the ratios between the values of protein deficiencies may be helpful in providing additional data about the clinical outcome of HS

    Cost-Effectiveness Analysis of Insulin Detemir Compared to Neutral Protamine Hagedorn (NPH) in Patients with Type 1 and Type 2 Diabetes Mellitus in Spain

    Get PDF
    Introduction: An Excel® (Microsoft Corporation) model was adapted to estimate the short-term (1-year) cost effectiveness of insulin detemir (IDet) versus neutral protamine Hagedorn (NPH) insulin in patients initiating insulin treatment with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) in Spain. Methods: Clinical benefits included the non-severe hypoglycemia rate for T1DM and T2DM, and weight change for T2DM. Three scenarios were included with different hypoglycemia rates estimated on the basis of clinical trials and observational studies. Costs, estimated from perspective of the Spanish Public Healthcare System (Euros 2014), included insulin treatment and non-severe hypoglycemia management costs. Non-severe hypoglycemia, defined as a self-managed event, implied the use of extra glucose testing strips and a general practitioner visit during the week following the event for 25% of patients. An average disutility value was associated to non-severe hypoglycemia events and, for T2DM, to one body mass index unit gain to calculate quality-adjusted life years (QALYs). Results: For the three scenarios a range of 0.025–0.076 QALYs for T1DM and 0.014–0.051 QALYs for T2DM were gained for IDet versus NPH due to non-severe hypoglycemia and weight gain avoidance, in return of an incremental cost of €145–192 for T1DM and €128–206 for T2DM. This resulted in the IDet versus NPH incremental cost-effectiveness ratio (ICER) ranging between €1910/QALY and €7682/QALY for T1DM and €2522/QALY and €15,009/QALY for T2DM. Conclusion: IDet was a cost-effective alternative to NPH insulin in the first year of treatment of patients with T1DM and patients with T2DM in Spain, with ICERs under the threshold value commonly accepted in Spain (€30,000/QALY)

    Reproduction of Gastric Cancer Prognostic Score by real-time quantitative polymerase chain reaction assay in an independent cohort

    Get PDF
    Purpose Addition of molecular markers to the American Joint Committee on Cancer (AJCC) staging system would allow further refinements in predicting recurrence and help individualize treatment decisions. We aimed to validate the Gastric Cancer Prognostic Score (GCPS) in an independent cohort using an easy and cost effective quantitative real-time polymerase chain reaction (qRT-PCR) assay. Methods We performed qRT-PCR using 48 samples from our previous study and expanded to 128 independent patients. The GCPS was recalculated using Cox regression estimates and the performance of cutoff values for GCPS was reassessed. Results The qRT-PCR results showed a similar pattern to nanostring data by scale function data comparison. Using a new cutoff value, GCPS stratified 95 stage IB–III patients who received adjuvant chemotherapy into 74 high-risk patients and 21 low-risk patients with significantly different recurrence-free survival (P< 0.0001). The survival difference remained significant (P= 0.028) in 27 patients who did not receive adjuvant chemotherapy. Among stage I and II patients who were treated with surgery only, one AJCC stage IIA patient was defined as low-risk and showed long-term survival. Nine of 12 high-risk patients showed recurrence less than 67 months after operation. Conclusion We reproduced the GCPS with an easily applicable qRT-PCR assay and successfully predicted recurrence in patients with gastric cancer

    Reversal of type 2 diabetes: normalisation of beta cell function in association with decreased pancreas and liver triacylglycerol

    Get PDF
    The presence of Fc-receptor-blocking factors in the sera of normal and insulin-dependent diabetic pregnant women was investigated by means of an antibody-dependent cell-mediated cytotoxicity assay. Sera from normal pregnant women induced a significant depression of antibody dependent cell-mediated cytotoxicity when compared with sera from normal and diabetic non-pregnant women (p less than 0.0001; p less than 0.002, respectively). The effect of sera from diabetic pregnant women, however, was not different from that observed with sera from normal and diabetic non-pregnant women. Thus, we confirm the presence of Fc-receptor-blocking factors in the sera of normal pregnant women. The higher cytotoxicity levels measured in the presence of sera from pregnant women with insulin-dependent diabetes suggests that the titres of such factors are reduced in this conditio
    corecore