123 research outputs found

    Data Transparent and Polarization Insensitive All-Optical Switch based on Fibers with Enhanced Nonlinearity

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    We have developed a data transparent optical packet switch prototype employing wavelength conversion based on four-wave mixing. The switch is composed of an electro-optical control unit and an all-optical switching segment. To achieve higher switching efficiencies, Ge-doped silica suspended-core and chalcogenide arsenicselenide single-mode fibers were experimentally evaluated and compared to conventional highly-nonlinear fiber. Improved connectorization technology has been developed for Ge-doped suspended-core fiber, where we achieved connection losses of 0.9 dB. For the arsenic-selenide fiber we present a novel solid joint technology, with connection losses of only 0.25 dB, which is the lowest value presented up-to-date. Conversion efficiency of -13.7 dB was obtained for the highly-nonlinear fiber, which is in perfect correlation with previously published results and thus verifies the functionality of the prototype. Conversion efficiency of -16.1 dB was obtained with arsenic-selenide fiber length reduced to five meters within simulations, based on measurement results with a 26 m long component. Employment of such a short arsenic-selenide fiber segment allows significant broadening of the wavelength conversion spectral range due to possible neglection of dispersion

    A Mixed Methods Study on CBAM and the Adoption of Thin Client Computers by Adolescents

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    Although stages of change and adoption of innovation dynamics have been examined for adult populations, comparable research for adolescents is limited. Applying a change instrument grounded in Concerns-Based Adoption Model (CBAM) to an adolescent population, this study investigates perceptions of 45 middle school students who used thin client portable computers in a one-to-one program at home and at school for 3 years. A mixed methodology design identified which of the 7 stages of concern students passed through and why some students adopted the innovation more readily than others. The Change Facilitator Stages of Concern Questionnaire, a modified version of CBAM, was used to collect quantitative data from students at the beginning and at the end of 6th grade. Qualitative interviews from 8 purposively selected students, their parents, and their teachers supplemented the survey data in the final year of the program. To guide this study, three questions were investigated: (1) What stages of concern were evident? (2) To what extent can variation in these stages of concern be explained by select demographic measures? (3) Based on the qualitative interviews, how do select students describe their adoption? Three distinct adoption pathways emerged in both the population and the sample. In Pathway 1, progressions occurred from lower to higher stages; in Pathway 2, no change between Pre- and Posttests; and in Pathway 3, backwards movement occurred through the stages. Unexpectedly, only 5 of the 7 stages of change were high stage scores. Regression analysis also revealed two significant findings: first, in the posttest analysis, the dependent variable (free lunch) suggested that poverty levels may influence a slower progression through CBAM stages; and second, there was a significant difference in pre- and posttest second high stage scores for the dependent variable (gender), suggesting that adolescent males gained nearly two more stages of change than did females. This study appears to be the first adaptation of the Change Facilitator Stages of Concern for adolescents. Both quantitative and qualitative evidence explained that adolescent pathways differ fundamentally from those of adults

    E-prosiding Sistek (seminar nasional teknologi): "Inovasi riset engineering berkelanjutan menuju kemandirian pembangunan bangsa" (

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    Prosiding Seminar Nasional Teknologi 2020 Fakultas Teknik Universitas Merdeka Malang dengan tema: "Inovasi riset engineering berkelanjutan menuju kemandirian pembangunan bangsa" sukses terselenggara di Malang pada hari Selasa, 10 November 2020. pengambilan tema tersebut berkaitan dengan semakin pesatnya perkembangan ilmu pengetahuan dan teknologi di abad 21 yang turut melahirkan perubahan ataupun pembaharuan di berbagai bidang kehidupan, tidak terkecuali bidang teknologi. Di Prosiding ini terdapat 35 pemakalah dari berbagai institusi pendidikan tinggi yang berasal dari Jawa Barat, Jawa Tengah, DI Yogyakarta serta Jawa Timur yang terbagi dalam 5 bidang keilmuan yaitu bidang teknik sipil (tema: Rekayasa Infrastruktur berbasis manajemen resiko bencana), teknik mesin (tema: Rekayasa desain energi baru terbarukan berbasis teknologi material dan manufaktur di era revolusi industri 4.0), arsitektur (tema: Konsep arsitektur hijau dalam konteks Urban dan Rural), teknik industri (tema: Teknologi dan rekayasa sistem industri, ergonomi serta distribusi di era disrupsi revolusi industri), dan teknik elektro (Teknologi internet of thing (IOT) dan robotika pada era industri 4.0

    Predictive value of respiratory symptoms and bronchial hyperresponsiveness to diagnose asthma in New Zealand

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    SummaryRespiratory symptoms are often used as the only diagnostic criteria for asthma in epidemiological surveys and the clinical diagnosis of asthma relies primarily on a detailed history. The aim of this study is to predict the diagnostic value of 11 different respiratory symptoms to diagnose asthma, and to determine if bronchial hyperresponsiveness (BHR) improves the predictive value of these respiratory symptoms.A random sample of 1257 subjects aged 20–44 years old in 3 different areas of New Zealand were selected between March 1991 and December 1992 to answer the European Community Respiratory Health Survey questionnaire on respiratory symptoms. Of these, 784 underwent bronchial challenge with methacholine. The prevalence of current doctor diagnosed asthma (DDA) defined as asthma confirmed by a physician and an asthma attack in the last 12 months was 8.3%. Wheezing with dyspnoea is the single best predictor of diagnosed asthma with a sensitivity of 82%, a specificity of 90% and a Youden's index of 0.72. Wheezing alone is more sensitive (94%) but less specific (76%), with a Youden's index of 0.70. The addition of BHR to asthma symptoms decreases sensitivity and increases specificity with a small increase in Youden's index to 0.75. In New Zealand adults, a history of wheezing with BHR best predicts a diagnosis of asthma but wheezing alone or with dyspnoea are the two best symptoms for predicting asthma

    Development of a real-time PCR assay for the specific detection and identification of Streptococcus pseudopneumoniae using the recA gene

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    AbstractWe sequenced the evolutionarily conserved genes 16S rRNA, atpD, tuf, and recA from Streptococcus pseudopneumoniae, Streptococcus pneumoniae, Streptococcus mitis, and Streptococcus oralis. Phylogenetic analysis revealed that recA provided good resolution between these species, including discrimination of the novel species S. pseudopneumoniae. By contrast, the more conserved 16S rRNA, tuf and atpD are not sufficiently discriminatory. Therefore, recA sequences were used to develop a real-time PCR assay with a locked nucleic acid-mediated TaqMan probe for the specific detection and identification of S. pseudopneumoniae. The PCR assay showed excellent specificity and a detection limit of <10 genome copies for the detection and identification of S. pseudopneumoniae strains, which makes it a promising tool for molecular identification and epidemiological studies. In conclusion, this article describes for the first time a PCR assay for the specific identification of S. pseudopneumoniae

    Prevalence of gastro-oesophageal reflux disease symptoms and reflux-associated respiratory symptoms in asthma

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    <p>Abstract</p> <p>Background</p> <p>Gastro-oesophageal reflux disease (GORD) symptoms are common in asthma and have been extensively studied, but less so in the Asian continent. Reflux-associated respiratory symptoms (RARS) have, in contrast, been little-studied globally. We report the prevalence of GORD symptoms and RARS in adult asthmatics, and their association with asthma severity and medication use.</p> <p>Methods</p> <p>A cross-sectional analytical study. A validated interviewer-administered GORD scale was used to assess frequency and severity of seven GORD symptoms. Subjects were consecutive asthmatics attending medical clinics. Controls were matched subjects without respiratory symptoms.</p> <p>Results</p> <p>The mean (SD) composite GORD symptom score of asthmatics was significantly higher than controls (21.8 (17.2) versus 12.0 (7.6); <it>P </it>< 0.001) as was frequency of each symptom and RARS. Prevalence of GORD symptoms in asthmatics was 59.4% (95% CI, 59.1%-59.6%) versus 28.5% in controls (95% CI, 29.0% - 29.4%). 36% of asthmatics experienced respiratory symptoms in association with both typical and atypical GORD symptoms, compared to 10% of controls (<it>P </it>< 0.001). An asthmatic had a 3.5 times higher risk of experiencing a GORD symptom after adjusting for confounders (OR 3.5; 95% CI 2.5-5.3). Severity of asthma had a strong dose-response relationship with GORD symptoms. Asthma medication use did not significantly influence the presence of GORD symptoms.</p> <p>Conclusions</p> <p>GORD symptoms and RARS were more prevalent in a cohort of Sri Lankan adult asthmatics compared to non-asthmatics. Increased prevalence of RARS is associated with both typical and atypical symptoms of GORD. Asthma disease and its severity, but not asthma medication, appear to influence presence of GORD symptoms.</p

    Prevalence of asthma symptoms based on the European Community Respiratory Health Survey questionnaire and FENO in university students: gender differences in symptoms and FENO

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    <p>Abstract</p> <p>Background</p> <p>The fractional concentration of nitric oxide in exhaled air (F<smcaps>E</smcaps>NO) is used as a biomarker of eosinophilic airway inflammation. F<smcaps>E</smcaps>NO is increased in patients with asthma. The relationship between subjective asthma symptoms and airway inflammation is an important issue. We expected that the subjective asthma symptoms in women might be different from those in men. Therefore, we investigated the gender differences of asthma symptoms and F<smcaps>E</smcaps>NO in a survey of asthma prevalence in university students.</p> <p>Methods</p> <p>The information about asthma symptoms was obtained from answers to the European Community Respiratory Health Survey (ECRHS) questionnaire, and F<smcaps>E</smcaps>NO was measured by an offline method in 640 students who were informed of this study and consented to participate.</p> <p>Results</p> <p>The prevalence of asthma symptoms on the basis of data obtained from 584 students (266 men and 318 women), ranging in age from 18 to 24 years, was analyzed. Wheeze, chest tightness, an attack of shortness of breath, or an attack of cough within the last year was observed in 13.2% of 584 students. When 38.0 ppb was used as the cut-off value of F<smcaps>E</smcaps>NO to make the diagnosis of asthma, the sensitivity was 86.8% and the specificity was 74.0%. F<smcaps>E</smcaps>NO was ≥ 38.0 ppb in 32.7% of students. F<smcaps>E</smcaps>NO was higher in men than in women. The prevalence of asthma symptoms estimated by considering F<smcaps>E</smcaps>NO was 7.2%; the prevalence was greater in men (9.4%) than women (5.3%). A F<smcaps>E</smcaps>NO ≥ 38.0 ppb was common in students who reported wheeze, but not in students, especially women, who reported cough attacks.</p> <p>Conclusions</p> <p>The prevalence of asthma symptoms in university students age 18 to 24 years in Japan was estimated to be 7.2% on the basis of F<smcaps>E</smcaps>NO levels as well as subjective symptoms. Gender differences were observed in both F<smcaps>E</smcaps>NO levels and asthma symptoms reflecting the presence of eosinophilic airway inflammation.</p> <p>Trial registration number</p> <p>UMIN000003244</p
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