10 research outputs found

    Spindle-shaped CeO2/biochar carbon with oxygen-vacancy as an effective and highly durable electrocatalyst for oxygen reduction reaction

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    Highly durable and active CeO2 on biochar carbon (CeO2/BC) derived from Spirulina platensis microalgae and synthesized by simple one-pot hydrothermal treatment and further activated through pyrolysis approach. A spindle-shaped morphology of CeO2 with predominant (111) facet was evidently observed from X-ray diffraction patterns and electron microscopy images. The structural features such as high specific surface area, defect-rich carbon with N & P atoms, increased oxygen vacancy and π-electron transfer play an important role for the improved oxygen reduction reaction (ORR). The considerable amount of Ce3+ and higher proportion of pyridinic N and graphitic N species are substantially contributed to the superior ORR performance of CeO2/BC700, which surpasses other similar catalysts and competing with Pt/C. Hence, the significant kinetic ORR parameters and extended stability (no loss after 5000 potential cycles) of the CeO2/BC700 catalysts provides the promising insight to develop the rare-earth metal oxide nanostructures as a possible candidate for ORR in alkaline medium

    Meridional wind derived from HF doppler radar and ionosonde over the magnetic equator

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    367-372The nature of plasma motion in the F-region at the magnetic equator is such that they are driven by the neutral air wind along the geomagnetic field. The meridional wind at the equatorial F-region is evaluated using HF Doppler radar of the Kerala University. Trivandrum (8.6° N, 77° E, dip 0.5° N) operated in spaced receiver configuration and ionosonde at equatorial station Trivandrum and an off-equatorial station Sriharikota (SHAR. 13.7° N, 80.2 °E, dip 10° N) for a few days during 1994- 1995. The meridional component of the plasma drift at the magnetic equator is determined from the HF Doppler radar data by finding the time delay between the signals received at the central and north antennae by cross-correlation method. The thermospheric meridional wind is also determined by using hʹF values obtained from the ionograms of both Trivandrum and Sriharikota. The temporal variation of meridional wind at the magnetic equator as determined by using both the HF Doppler and ionosonde methods show similar pattern. These results are compared with that obtained using HWM93. It was found that the magnitude of the poleward wind and its time of reversal depend on the altitude of the ionospheric layer

    Long-term effectiveness of dopamine agonists and monoamine oxidase B inhibitors compared with levodopa as initial treatment for Parkinson\u27s disease (PD MED): A large, open-label, pragmatic randomised trial

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    \ua9 2014 Elsevier Ltd. Background Whether initial treatment for Parkinson\u27s disease should consist of levodopa, dopamine agonists, or monoamine oxidase type B inhibitors (MAOBI) is uncertain. We aimed to establish which of these three classes of drug, as initial treatment, provides the most effective long-term control of symptoms and best quality of life for people with early Parkinson\u27s disease. Methods In this pragmatic, open-label randomised trial, patients newly diagnosed with Parkinson\u27s disease were randomly assigned (by telephone call to a central office; 1:1:1) between levodopa-sparing therapy (dopamine agonists or MAOBI) and levodopa alone. Patients and investigators were not masked to group assignment. Primary outcomes were the mobility dimension on the 39-item patient-rated Parkinson\u27s disease questionnaire (PDQ-39) quality-of-life scale (range 0-100 with six points defined as the minimally important difference) and cost-effectiveness. Analysis was intention to treat. This trial is registered, number ISRCTN69812316. Findings Between Nov 9, 2000, and Dec 22, 2009, 1620 patients were assigned to study groups (528 to levodopa, 632 to dopamine agonist, 460 to MAOBI). With 3-year median follow-up, PDQ-39 mobility scores averaged 1\ub78 points (95% CI 0\ub75-3\ub70, p=0\ub7005) better in patients randomly assigned to levodopa than those assigned to levodopa-sparing therapy, with no increase or attrition of benefit during 7 years\u27 observation. PDQ-39 mobility scores were 1\ub74 points (95% CI 0\ub70-2\ub79, p=0\ub705) better in patients allocated MAOBI than in those allocated dopamine agonists. EQ-5D utility scores averaged 0\ub703 (95% CI 0\ub701-0\ub705; p=0\ub70002) better with levodopa than with levodopa-sparing therapy; rates of dementia (hazard ratio [HR] 0\ub781, 95% CI 0\ub761-1\ub708, p=0\ub714), admissions to institutions (0\ub786, 0\ub763-1\ub718; p=0\ub74), and death (0\ub785, 0\ub769-1\ub706, p=0\ub717) were not significantly different, but the upper CIs precluded any substantial increase with levodopa compared with levodopa-sparing therapy. 179 (28%) of 632 patients allocated dopamine agonists and 104 (23%) of 460 patients allocated MAOBI discontinued allocated treatment because of side-effects compared with 11 (2%) of 528 patients allocated levodopa (p<0\ub70001). Interpretation Very small but persistent benefits are shown for patient-rated mobility scores when treatment is initiated with levodopa compared with levodopa-sparing therapy. MAOBI as initial levodopa-sparing therapy was at least as effective as dopamine agonists. Funding UK National Institute for Health Research Health Technology Assessment Programme and UK Department of Health

    A comprehensive review of MXenes

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    Association of TLR1, TLR2, TLR4, TLR6, and TIRAP polymorphisms with disease susceptibility

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