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The effect of complexing agents on Co oxidation/dissolution in alkaline solution was investigated for Co chemical-mechanical polishing (CMP) and post-CMP cleaning processes. The oxidation and dissolution properties of Co in a solution are greatly affected by complexing agents, which could influence the performance of Co CMP and post-CMP cleaning processes. Herein, three complexing agents, glycine, ethylenediaminetetraacetic acid (EDTA), and citric acid were studied. It was revealed that the complexing agents determined Co dissolution rate depending on the presence or absence of H 2 O 2. Glycine showed a higher Co dissolution rate than EDTA and citric acid in the absence of H 2 O 2 , while EDTA showed the highest dissolution rate in the presence of H 2 O 2. Negligible dissolution was observed with citric acid, regardless of the presence of H 2 O 2. Electrochemical impedance and UV–Vis spectroscopies found that the difference in Co dissolution rates was related to Co oxidation rate and complexation capability of each complexing agent. Glycine showed a higher Co oxidation rate than EDTA, while EDTA had a much higher complexation capability than glycine. Citric acid exhibited the lowest Co oxidation rate and complexation capability, resulting in the slowest Co dissolution rate. Schematic diagram of dissolution rate of Co surface by different complexing agents, affected by oxidation rate and complexation capability. Unlabelled Image • The oxidation and dissolution property of Co surface is affected by complexing agents. • Glycine showed the highest dissolution rate of Co without H 2 O 2 due to better surface oxidation. • EDTA exhibited better dissolution rate than others in the presence of H 2 O 2 because of high complexation capability. • Citric acid deteriorated Co surface with H 2 O 2 during surface oxidation. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Dose-related effect of statins in patients with endovascular coiling or microsurgical clipping for aneurysmal subarachnoid hemorrhage: updated study-level meta-analysis" which appeared in the 2017 issue.

In this study, we developed a metal-free and highly chemoselective method for the reduction of aromatic nitro compounds. This reduction was performed using tetrahydroxydiboron [B 2 (OH) 4 ] as the reductant and 4,4'-bipyridine as the organocatalyst and could be completed within 5 min at room temperature. Under optimal conditions, nitroarenes with sensitive functional groups, such as vinyl, ethynyl, carbonyl, and halogen, were converted into the corresponding anilines with excellent selectivity while avoiding the undesirable reduction of the sensitive functional groups.

Development of a simple, effective, and practical method for (Z)-selective semihydrogenation of alkynes has been considered necessary for easy-to-access applications at organic laboratory scales. Herein, (Z)-selective semihydrogenation of alkynes was achieved using a copper nanocatalyst which was generated in situ simply by adding ammonia borane to an ethanol solution of copper sulfate. Different types of alkynes including aryl-aryl, aryl-alkyl, and aliphatic alkynes were selectively reduced to (Z)-alkenes affording up to 99% isolated yield. The semihydrogenation of terminal alkynes to alkenes and gram-scale applications were also reported. In addition to eliminating catalyst preparation, the proposed approach is simple and practical and serves as a suitable alternative method to the conventional Lindlar catalyst.

Suzuki-Miyaura (SM) cross-coupling is one of the most effective strategies for carbon-carbon bond formation, but previous methods have several drawbacks, such as the requirement of complicated ligands, toxic organic solvents, and high-content-Pd catalysts. Thus, in this study, a highly efficient SM cross-coupling was developed using metal oxide catalysts: 0.02 mol% Pd, aqueous solvent, no ligand, and room temperature. Metal oxides containing low Pd content (ppm scale) were prepared by a simple co-precipitation method and used as a catalyst for the SM reaction. A fluorescence-based high-throughput screening (HTS) method was developed for the rapid evaluation of catalytic activity and reaction conditions. Among the various metal oxides, Pd/Fe2O3 showed the highest activity for the SM reaction. After further optimization by HTS, various biaryl compounds were obtained under optimal conditions: Pd/Fe2O3 (0.02 mol% Pd) in aqueous ethanol at mild temperature without any ligands.

Methanol crossover is one of the largest problems in direct methanol fuel cells (DMFCs). Methanol passing from the anode to the cathode through the membrane is oxidized at the cathode, degrading the DMFC performance, and the intermediates of the methanol oxidation reaction (MOR) cause cathode catalyst poisoning. Therefore, it is essential to develop a cathode catalyst capable of inhibiting MOR while promoting the oxygen reduction reaction (ORR), which is a typical cathode reaction in DMFCs. In this study, a carbon-encapsulated Pt cathode catalyst was synthesized for this purpose. The catalyst was simply synthesized by heat treatment of Pt-aniline complex-coated carbon nanofibers. The carbon shell of the catalyst was effective in inhibiting methanol from accessing the Pt core, and this effect became more prominent as the graphitization degree of the carbon shell increased. Meanwhile, the carbon shell allowed O 2 to permeate regardless of the graphitization degree, enabling the Pt core to participate in ORR. The synthesized catalyst showed higher performance and stability in single-cell tests under various conditions compared to commercial Pt/C.

In this study, we developed a simple transition-metal-free borylation reaction of aryl bromides. Bis-boronic acid (BBA), was used, and the borylation reaction was performed using a simple procedure at a mild temperature. Under mild conditions, aryl bromides were converted to arylboronic acids directly without any deprotection steps and purified by conversion to trifluoroborate salts. The functional group tolerance was considerably high. The mechanism study suggested that this borylation reaction proceeds via a radical pathway.

Electrodeposition of Si films from a Si-containing electrolyte is a cost-effective approach for the manufacturing of solar cells. Proposals relying on fluoride-based molten salts have suffered from low product quality due to difficulties in impurity control. Here we demonstrate the successful electrodeposition of high-quality Si films from a CaCl 2 -based molten salt. Soluble Si IV -O anions generated from solid SiO 2 are electrodeposited onto a graphite substrate to form a dense film of crystalline Si. Impurities in the deposited Si film are controlled at low concentrations (both B and P are less than 1 ppm). In the photoelectrochemical measurements, the film shows p-type semiconductor character and large photocurrent. A p-n junction fabricated from the deposited Si film exhibits clear photovoltaic effects. This study represents the first step to the ultimate goal of developing a cost-effective manufacturing process for Si solar cells based on electrodeposition., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

TAM receptor tyrosine kinases (RTKs), Tyro3, Axl and MerTK, transduce diverse signals responsible for cell survival, growth, proliferation and anti-apoptosis. In the present study, we demonstrated the effect of luteolin, a flavonoid with antioxidant, anti-inflammatory and anticancer activities, on the expression and activation of TAM RTKs and the association with its cytotoxicity in non-small cell lung cancer (NSCLC) cells. We observed the cytotoxic effect of luteolin in parental A549 and H460 cells as well as in cisplatin-resistant A549/CisR and H460/CisR cells. Exposure of these cells to luteolin also resulted in a dose‑dependent decrease in clonogenic ability. Next, luteolin was found to decrease the protein levels of all three TAM RTKs in the A549 and A549/CisR cells in a dose‑dependent manner. In a similar manner, in H460 and H460/CisR cells, the protein levels of Axl and Tyro3 were decreased following luteolin treatment. In addition, Axl promoter activity was decreased by luteolin, indicating that luteolin suppresses Axl expression at the transcriptional level. We next found that luteolin abrogated Axl phosphorylation in response to growth arrest-specific 6 (Gas6), its ligand, implying the inhibitory effect of luteolin on Gas6-induced Axl activation. Ectopic expression of Axl was observed to attenuate the antiproliferative effect of luteolin, while knockdown of the Axl protein level using a gold nanoparticle-assisted gene delivery system increased its cytotoxicity. In contrast to the inhibitory effect of luteolin on the expression of TAM RTKs, interleukin-8 (IL-8) production was not decreased by luteolin in H460 and H460/CisR cells, while IL-8 production/cell was increased. Collectively, our data suggest that TAM RTKs, but not IL-8, are promising therapeutic targets of luteolin to abrogate cell proliferation and to overcome chemoresistance in NSCLC cells.

Purpose: Feedback devices are used to improve chest compression (CC) quality related to survival rates in cardiac arrest. However, several studies have shown that feedback devices are not sufficiently reliable to ensure adequate CC depth on soft surfaces. Here, we determined the proper target depth of feedback (TDF) using an accelerometer during cardiopulmonary resuscitation in hospital beds., Methods: In prospective randomized crossover study, 19 emergency physicians performed CCs for 2 minutes continuously on a manikin in 2 different beds with 3 TDFs (5, 6, and 7 cm). We measured CC depth, the proportion of accurate compression depths, CC rate, the proportion of incomplete chest decompressions, the velocity of CC (CC velocity), the proportion of time spent in CC relative to compression plus decompression (duty cycle), and the time spent in CC (CC time)., Results: Mean (SD) CC depths at TDF 5, 6, and 7 were 45.42 (5.79), 52.68 (4.18), and 58.47 (2.48) on one bed and 46.26 (4.49), 53.58 (3.15), and 58.74 (2.10) mm on the other bed (all P<.001), respectively. The proportions of accurate compression depths and CC velocity at TDF 5, 6, and 7 differed significantly according to TDF on both beds (all P<.001).The CC rate, CC time, and proportion of incomplete chest decompression did not differ on both beds (all P>.05). The duty cycle differed significantly on only B2., Conclusions: The target depth of the real-time feedback device should be at least 6 cm but should not exceed 7 cm for optimal CC on patients on hospital beds., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: The learning curve-cumulative summation (LC-CUSUM) test allows for quantitative and individual assessments of the learning process. In this study, we evaluated the process of skill acquisition for performing endotracheal intubation (ETI) in three emergency medicine (EM) residents over a 2 year period in their first 2 years of their EM residency., Methods: We evaluated 342 ETI cases performed by three EM residents using the LC-CUSUM test according to their rate of success or failure of ETI. A 90% success rate (SR) was chosen to define adequate performance and an SR of 80% was considered inadequate. After the learning phase, the standard CUSUM test was applied to ensure that performance was maintained., Results: The mean number of ETI cases required to reach the predefined level of performance was 74.7 (95% CI 62.0 to 87.3). CUSUM tests confirmed that performance was maintained after the learning phase., Conclusions: By using the LC-CUSUM test, we were able to quantitatively monitor the acquisition of the skill of ETI by EM residents. The LC-CUSUM could be useful for monitoring the learning process for the training of airway management in the practice of EM., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Purpose: We suggest an alternative chest compression (CC) in kneeling posture using a 'kneeling stool' on which the performer kneels beside the patient on a bed in-hospital. In kneeling posture, we can maintain high quality cardiopulmonary resuscitation (CPR) without the bed height adjustment, which is necessary and inconvenient in standing posture., Methods: This study is a randomised crossover trial with 38 participants working in one ED. The first group knelt on the kneeling stool beside a manikin placed on a bed, whereas the second group stood on a step stool with the manikin at knee level using bed height adjustment. All the participants performed continuous chest compression for 5 min without audio-visual feedback. After that, the posture was changed in each group. The parameters of CC quality (CC depth, rate, accuracy, and incomplete chest recoil), visual analogue scale (VAS) for fatigue and pain, and preference of participants were compared between the two groups., Results: The data of 33 participants in both postures were analysed following exclusion of five participants. In the comparisons overall and per minute between the two postures, the parameters and VAS do not differ significantly (all P > 0.05) except for the median 1st CC rate that was faster in kneeling posture than in standing posture, P = 0.01). Twenty-three performers preferred the kneeling posture., Conclusions: A kneeling posture with a kneeling stool were preferred by participants, which have shown similar results in CC parameters and VAS with a standing posture on a stepstool with bed height adjustment during in-hospital CPR., (© 2014 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.)

Purpose: We hypothesized that novices would be able to use the McGrath MAC (Aircraft Medical Ltd, Edinburgh, UK) equally as well as the GlideScope Ranger (Verathon, Inc, Bothell, WA) for intubation in regular simulated airways., Methods: We performed a prospective, randomized crossover study of 39 medical students using the McGrath MAC, GlideScope Ranger, and Macintosh in a manikin with 2 normal airways. The primary outcome was the intubation time. Secondary outcomes included the success rates and the overall glottic view of the 3 laryngoscopes., Results: The mean intubation times for each attempt with the McGrath MAC were 30.8 ± 16.9 seconds or less and did not differ significantly from those obtained with the GlideScope Ranger or the Macintosh in both airway scenarios (P = .18; P = .49). The mean success rates at each attempt with the McGrath MAC were 82.0% ± 38.8% or more, equal to the Macintosh and the GlideScope Ranger in both scenarios (P = .026; P = .72) except during the first intubation attempt in a normal airway (P = .008). The median grades of the glottic view visible at each intubation attempt with the McGrath Mac were Cormack-Lehane grade 1 (scenario 1: interquartile range, 1-1; scenario 2: interquartile range, 1-2), which was significantly better than the Macintosh laryngoscope in both scenarios. However, the McGrath Mac did not produce a better glottic view than the GlideScope Ranger with either scenario., Conclusions: The intubation performance of novices using the McGrath MAC was equal to their performance using the GlideScope Ranger in regular simulated airways., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: This study is a feasibility assessment to determine the ability of novice users to utilize an infrared (IR) sensor stylet as a guide to position the tip of the endotracheal tube (ETT) 40 mm proximal to the carina in the swine trachea., Methods: We developed a stylet system using an IR sensor attached to the tip of a stylet to facilitate measuring the distance of the ETT from the carina. The indicator lamp of the IR sensor system turns on through calibration when the ETT tip arrives at a point 20 mm proximal to the carina. In order to place the ETT tip 40 mm (middle of 20-60 mm) from the carina after the indicator lamp turns on, the operator uses the ETT marker to withdraw the ETT 20 mm. For this study, five fresh swine airways were used in random order after drawing lots, and ten novices were recruited to attempt the procedure ten times on each swine's airway., Results: Five hundred endotracheal intubations were performed. For the target distance of 40 mm from the ETT tip to the carina, the mean (standard deviation) of the total data set was 37.9 (3.5) mm; all data were within a 20-60 mm range (500/500), and 98.2% (491/500) of the attempts fell within the 30-50 mm range., Conclusions: The IR sensor stylet system can facilitate correct positioning of the ETT tip at an appropriate depth above the carina in the swine trachea. Evaluation of the IR sensor stylet methodology in human subjects is warranted.

Study Objective: Cricoid pressure may negatively affect laryngeal view and compromise airway patency, according to previous studies of direct laryngoscopy, endoscopy, and radiologic imaging. In this study, we assess the effect of cricoid pressure on laryngeal view with a video laryngoscope, the Pentax-AWS., Methods: This cross-sectional survey involved 50 American Society of Anesthesiologists status I and II patients who were scheduled to undergo elective surgery. The force measurement sensor for cricoid pressure and the video recording system using a Pentax-AWS video laryngoscope were newly developed by the authors. After force and video were recorded simultaneously, 11 still images were selected per 5-N (Newton; 1 N = 1 kg·m·s(-2)) increments, from 0 N to 50 N for each patient. The effect of cricoid pressure was assessed by relative percentage compared with the number of pixels on an image at 0 N., Results: Compared with zero cricoid pressure, the median percentage of glottic view visible was 89.5% (interquartile range [IQR] 64.2% to 117.1%) at 10 N, 83.2% (IQR 44.2% to 113.7%) at 20 N, 76.4% (IQR 34.1% to 109.1%) at 30 N, 51.0% (IQR 21.8% to 104.2%) at 40 N, and 47.6% (IQR 15.2% to 107.4%) at 50 N. The number of subjects who showed unworsened views was 20 (40%) at 10 N, 17 (34%) at 20 and 30 N, and 13 (26%) at 40 and 50 N., Conclusion: Cricoid pressure application with increasing force resulted in a worse glottic view, as examined with the Pentax-AWS Video laryngoscope. There is much individual difference in the degree of change, even with the same force. Clinicians should be aware that cricoid pressure affects laryngeal view with the Pentax-AWS and likely other video laryngoscopes., (Copyright © 2012. Published by Mosby, Inc.)

In order to ensure that high-quality cardio-pulmonary-resuscitation (CPR) is performed, many kinds of feedback devices have been developed that are helpful for achieving correct chest compression (CC) in manikin studies. However, the mattress compression depth (MCD) can cause overestimation of chest compression depth (CCD) during CPR using a feedback device. Herein, we propose a new method using a vinyl cover that encloses the foam mattress and is compressed by vacuum pump just before performing CPR, which could increase the performance of CCs during CPR.