Extremely active palladium-based alloys catalysts without platinum for the oxygen reduction reaction (ORR) in an acid medium were shown for the first time. The palladium alloys were prepared by ...sputtering under a vacuum of less than 10
−4 Pa from a palladium target and an alloying metal sheets on a glassy carbon support. Their electrochemical characteristics for ORR were determined at 30 °C in sulphuric acid. It was demonstrated that the base voltammograms (CVs) of Pd–Co alloys did not show significant change in the shape or size during the whole measurements procedure. Furthermore the Pd–Co alloy CV were found to be completely different from those of Pd and Co alone and they never changed to become more Pd-like or Co-like. The Pd–Co alloy catalysts are stable under the applied experimental conditions. The interesting properties of the alloys for the ORR were attributed to an appropriate electronic stabilisation of the alloying element atom in the alloy which may prevent its corrosion and which allows the enhancement of its catalytic activity. It was further demonstrated that an improvement of at least 250 mV, based only on a theoretical estimation from Tafel slope, in ORR over-voltage could be obtained if a Pd–Co 28% catalyst is used at 30 °C instead of Pt for PEFC or acid Solid Polymer Electrolyser Applications.
One of the challenges faced by Brazilian distribution utilities to enable the connection and operation of microgrids (MGs) is the absence of a solid set of technical standards in the country. An ...alternative has been to use and adapt existing standards applied to micro- and mini-distributed generation. In this context, this paper presents an analysis of the development status of norms, standards, and general requirements for the connection and operation of microgrids, as well as a proposal for the regulation and structuring of technical and operational requirements related to the implementation of microgrid projects. Some critical points highlighted in the paper include: the modes of operation, the minimum requirements for the different modes of operation, interoperability of systems, a conceptual model with attribution of responsible actors for the decentralized management of microgrids adapted to the institutional standards of the Brazilian sectorial model, a proposal for a standard connection structure considering the point of connection (PoC) implanted using multifunctional relay and recloser, procedures for technical feasibility assessment (operational studies) of MGs connection, and, finally, a discussion of operational issues of storage systems in a microgrid environment.
Recent preclinical and phase I studies have reported that rebamipide decreased the severity of chemoradiotherapy-induced oral mucositis in patients with oral cancer. This placebo-controlled ...randomized phase II study assessed the clinical benefit of rebamipide in reducing the incidence of severe chemoradiotherapy-induced oral mucositis in patients with head and neck cancer (HNC).
Patients aged 20-75 years with HNC who were scheduled to receive chemoradiotherapy were enrolled. Patients were randomized to receive rebamipide 2% liquid, rebamipide 4% liquid, or placebo. The primary endpoint was the incidence of grade ≥ 3 oral mucositis determined by clinical examination and assessed by central review according to the Common Terminology Criteria of Adverse Events version 3.0. Secondary endpoints were the time to onset of grade ≥ 3 oral mucositis and the incidence of functional impairment (grade ≥ 3) based on the evaluation by the Oral Mucositis Evaluation Committee.
From April 2014 to August 2015, 97 patients with HNC were enrolled, of whom 94 received treatment. The incidence of grade ≥ 3 oral mucositis was 29% and 25% in the rebamipide 2% and 4% groups, respectively, compared with 39% in the placebo group. The proportion of patients who did not develop grade ≥ 3 oral mucositis by day 50 of treatment was 57.9% in the placebo group, whereas the proportion was 68.0% in the rebamipide 2% group and 71.3% in the rebamipide 4% group. The incidences of adverse events potentially related to the study drug were 16%, 26%, and 13% in the placebo, rebamipide 2%, and rebamipide 4% groups, respectively. There was no significant difference in treatment compliance among the groups.
The present phase II study suggests that mouth washing with rebamipide may be effective and safe for patients with HNC receiving chemoradiotherapy, and 4% liquid is the optimal dose of rebamipide.
ClinicalTrials.gov under the identifier NCT02085460 (the date of trial registration: March 11, 2014).
This paper provides an experimental discussion on zero-voltage-ride-through (ZVRT) capability of a phase-shifted pulsewidth-modulation distribution static synchronous compensator (D-STATCOM) using ...the modular multilevel cascade converter based on single-star bridge cells (SSBC). The cluster-balancing control producing a significant effect on the ZVRT capability is modeled and analyzed with focus on either a low-pass filter (LPF) or a moving-average filter (MAF) to attenuate the 100-Hz (double the line frequency) component inherent in each dc capacitor voltage. The cluster-balancing control using the MAF is better in transient performance than that using the LPF. A three-phase downscaled SSBC-based D-STATCOM rated at 150 V and 10 kVA is designed, constructed, and tested to verify the ZVRT capability under the severest single-, two-, and three-phase voltage sags with a voltage depth of 100%. Experimental waveforms show that the STATCOM continues operating stably as if no voltage sag occurred.
This paper presents and discusses a phase-shifted-PWM distribution static synchronous compensator (D-STATCOM) using the modular multilevel cascade converter based on single-star bridge cells ...(MMCC-SSBC). A three-phase 140-V 10-kVA SSBC-based STATCOM with a cascade count N=6 is designed, constructed, and tested for verifying the performance and functionality of the medium-voltage D-STATCOM in both steady and transient states. The 13-level line-to-neutral (25-level line-to-line) voltage at the ac side yields an almost sinusoidal line current with a total harmonic distortion value of 1.7%. An analytical model for the phase-shifted PWM is proposed to design the current control gains. Two phase-shifted PWM methods, which are named as one-cell and all-cells update methods, are theoretically and experimentally compared. The all-cells update method can reduce the inherent time delay, thus resulting in a faster and more stable system response than the one-cell update method.
Summary
Epidermal growth factor receptor inhibitors (EGFRIs) frequently cause cutaneous adverse effects such as papulopustular eruptions. However, the mechanism of the reactions remains unclear. To ...assess the pathological mechanism of cutaneous adverse reactions caused by EGFRIs, we investigated whether EGFRIs have an influence on the innate immune response of the skin. Levels of human β‐defensins (hBDs), which serve as the first line of defence against infection by pathogenic microorganisms, in the stratum corneum samples of patients treated with EGFR. monoclonal antibodies were measured before and after starting therapy. There were no obvious trends in hBD production in patients without eruptions, whereas a significant decrease in hBD1 and hBD3 production and a nonsignficant decrease in hBD2 production were observed in patients who developed papulopustular eruptions. Our results suggest that a reduction in hBD contributes to the increased incidence of papulopustular eruptions.
Previous work has shown that a fusion protein bearing a “nonremovable” N-terminal ubiquitin (Ub) moiety is short-lived in vivo, the fusion's Ub functioning as a degradation signal. The proteolytic ...system involved, termed the UFD pathway (Ub fusion degradation), was dissected in the yeast Saccharomyces cerevisiae by analyzing mutations that perturb the pathway. Two of the five genes thus identified, UFD1 and UFD5, function at post-ubiquitination steps in the UFD pathway. UFD3 plays a role in controlling the concentration of Ub in a cell: ufd3 mutants have greatly reduced levels of free Ub, and the degradation of Ub fusions in these mutants can be restored by overexpressing Ub. UFD2 and UFD4 appear to influence the formation and topology of a multi-Ub chain linked to the fusion's Ub moiety. UFD1, UFD2, and UFD4 encode previously undescribed proteins of 40, 110, and 170 kDa, respectively. The sequence of the last ∼280 residues of Ufd4p is similar to that of E6AP, a human protein that binds to both the E6 protein of oncogenic papilloma viruses and the tumor suppressor protein p53, whose Ub-dependent degradation involves E6AP. UFD5 is identical to the previously identified SON1, isolated as an extragenic suppressor of sec63 alleles that impair the transport of proteins into the nucleus. UFD5 is essential for activity of both the UFD and N-end rule pathways (the latter system degrades proteins that bear certain N-terminal residues). We also show that a Lys → Arg conversion at either position 29 or position 48 in the fusion's Ub moiety greatly reduces ubiquitination and degradation of Ub fusions to β-galactosidase. By contrast, the ubiquitination and degradation of Ub fusions to dihydrofolate reductase are inhibited by the UbR29 but not by the UbR48 moiety. ufd4 mutants are unable to ubiquitinate the fusion's Ub moiety at Lys29, whereas ufd2 mutants are impaired in the ubiquitination at Lys48. These and related findings suggest that Ub-Ub isopeptide bonds in substrate-linked multi-Ub chains involve not only the previously identified Lys48 but also Lys29 of Ub, and that structurally different multi-Ub chains have distinct functions in Ub-dependent protein degradation.
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