10 research outputs found
Observation of the Relationship between Ocean Bathymetry and Acoustic Bearing-Time Record Patterns Acquired during a Reverberation Experiment in the Southwestern Continental Margin of the Ulleung Basin, Korea
We observed a distinct drop-off region in the bearing-time record of acoustic reverberation data acquired from the south-western continental margin of the Ulleung Basin, East Sea, in the summer of 2015. 3 kHz continuous waves with pulse lengths of 0.1, 0.3, and 1.0 s were used as source pulses, with an R/V Cheonghae vessel towing a variable depth source and a triplet towed array toward the deep sea from shallow water. The observed pattern changed as the R/V Cheonghae moved across the continental slope further into the sea. This pattern arises as a result of the downward-refracted beams in the 1/2 convergence zone interacting with the soft bottom. In addition, the boundary of the drop-off region was modeled with the two-way maximum travel time of the first bottom-reflected rays using the bathymetry model of the General Bathymetric Chart of the Oceans, 2020. Some discrepancies were observed when comparing the modeled curve to the measured results, and the inaccuracy of the bathymetry model on the continental slope could be the main cause of these discrepancies. This pattern could be useful for bathymetry mapping, as well as estimations of source and receiver configurations
Supraglottic airway devices as a strategy for unassisted tracheal intubation: A network meta-analysis.
We aimed to compare the effectiveness of supraglottic airway devices as a strategy for unassisted tracheal intubation. Accordingly, we searched the OVID-MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, KoreaMed, and Google Scholar databases to identify all relevant randomized controlled trials (RCTs) on supraglottic airway devices as a strategy for tracheal intubation published until May 2017. The primary outcome was the overall success rate of intubation by the intention to treat (ITT) strategy. The secondary outcomes of the study were the overall success rate of tracheal intubation by the per protocol (PP) strategy and the success rate of tracheal intubation at first attempt by ITT and PP. We conducted a network meta-analysis with a mixed-treatment comparison method to combine direct and indirect comparisons among supraglottic airway devices. Of 1396 identified references, 16 RCTs (2014 patients) evaluated unassisted intubation with supraglottic airway devices. Patients were grouped according to the type of device used: LMA-CTrach, LMA-Fastrach, Air-Q, i-gel, CobraPLA, Ambu-Aura, or single-use LMA devices. Based on the surface under the cumulative ranking curve, the three best supraglottic airway devices for use as a strategy for unassisted tracheal intubation were LMA-CTrach (which included video-assisted tracheal tube guidance), single-use LMA-Fastrach, and LMA-Fastrach. LMA-Fastrach showed a higher success rate of intubation than did i-gel, CobraPLA, Air-Q, and Ambu-Aura. However, this study was limited by the small number of eligible RCTs. Therefore, well-designed RCTs performed on large patient populations are required to increase the confidence of the results
Function and Structure of a Terpene Synthase Encoded in a Giant Virus Genome
Giant viruses are nonstandard viruses with large particles
and
genomes. While previous studies have shown that their genomes contain
various sequences of interest, their genes related specifically to
natural product biosynthesis remain unexplored. Here we analyze the
function and structure of a terpene synthase encoded by the gene of
a giant virus. The enzyme is phylogenetically separated from the terpene
synthases of cellular organisms; however, heterologous gene expression
revealed that it still functions as a terpene synthase and produces
a cyclic terpene from a farnesyl diphosphate precursor. Crystallographic
analysis revealed its protein structure, which is relatively compact
but retains essential motifs of the terpene synthases. We thus suggest
that like cellular organisms, giant viruses produce and utilize natural
products for their ecological strategies
Palonosetron and Ramosetron Compared for Effectiveness in Preventing Postoperative Nausea and Vomiting: A Systematic Review and Meta-Analysis
<div><p>Previous randomized controlled trials have reported conflicting findings on the superiority of palonosetron over ramosetron for preventing postoperative nausea and vomiting (PONV). Therefore, the present systematic review was registered in PROSPERO (CRD42016038120) and performed to compare the efficacy of perioperative administration of palonosetron to that of ramosetron for preventing PONV. We searched MEDLINE, EMBASE, and CENTRAL to identify all randomized controlled trials that compared the effectiveness of perioperative administration of palonosetron to that of ramosetron. The primary endpoints were defined as the incidence of postoperative nausea (PON), postoperative vomiting (POV), and PONV. A total of 695 patients were included in the final analysis. Subgroup analysis was performed through administration times which were divided into two phases: the early phase of surgery and the end of surgery. Combined analysis did not show differences between palonosetron and ramosetron in the overall incidence of PON, POV or PONV. Palonosetron was more effective than ramosetron, when the administration time for the 5-HT<sub>3</sub> receptor antagonist was during the early phase of the operation. Otherwise, ramosetron was more effective than palonosetron, when the administration time was at the end of surgery. However, the quality of evidence for each outcome was low or very low and number of included studies was small, limiting our confidence in findings.</p></div
Forest plot for studies comparing the effect of palonosetron to that of ramosetron on overall POV.
<p>The figure depicts individual trials as filled squares with relative size of sample size and solid line as the 95% confidence interval of the difference. The diamond shape indicates the pooled estimate and uncertainty for the combined effect.</p
Forest plot for studies comparing the effect of palonosetron and to that of ramosetron on overall PONV when the administration time was at the end of surgery.
<p>The figure depicts individual trials as filled squares with relative size of sample size and solid line as the 95% confidence interval of the difference. The diamond shape indicates the pooled estimate and uncertainty for the combined effect.</p
Risk of Bias in the Included Randomized Controlled trials.
<p>Risk of Bias in the Included Randomized Controlled trials.</p
Data Extracted from the Included Studies.
<p>Data Extracted from the Included Studies.</p
Further Data Extracted from the Included Studies.
<p>Further Data Extracted from the Included Studies.</p