Electrochemical Analysis of Ion Effects on Electrolyte-Gated Synaptic Transistor Characteristics.

Electrolyte-gated transistors (EGTs) are promising candidates as artificial synapses owing to their precise conductance controllability, quick response times, and especially their low operating voltages resulting from ion-assisted signal transmission. However, it is still vague how ion-related physiochemical elements and working mechanisms impact synaptic performance. Here, to address the unclear correlations, we suggest a methodical approach based on electrochemical analysis using poly(ethylene oxide) EGTs with three alkali ions: Li+, Na+, and K+. Cyclic voltammetry is employed to identify the kind of electrochemical reactions taking place at the channel/electrolyte interface, which determines the nonvolatile memory functionality of the EGTs. Additionally, using electrochemical impedance spectroscopy and qualitative analysis of electrolytes, we confirm that the intrinsic properties of electrolytes (such as crystallinity, solubility, and ion conductivity) and ion dynamics ultimately define the linearity/symmetricity of conductance modulation. Through simple but systematic electrochemical analysis, these results offer useful insights for the selection of components for high-performing artificial synapses.

Structural Homogeneity of Macromolecular Networks by End-to-End Click Chemistry between Discrete Tetrahedral Star Macromolecules.

Cross-linking via the end-to-end click chemistry of multiarm star polymers creates polymer networks with minimal inhomogeneities. Although it has been suggested that the mechanical and swelling properties of such networks depend on the absence of defects, the structural details of homogeneous networks created by this method have not yet been studied at the molecular level. Here, we report the synthesis of discrete tetrahedral star macromolecules (dTSMs) composed of polylactide (PLA) arms with discrete molecular weight and sequence. Polymer networks prepared by 4 × 4 cross-linking by Cu-free strain-promoted cyclooctyne-azide click chemistry (SPAAC) reaction exhibited a high degree of swelling (>40 fold by weight) in solvents without sacrificing mechanical robustness (elastic modulus >4 kPa). The structural details of the networks were investigated by network disassembly spectrometry (NDS) using MALDI-TOF mass spectrometry. By implementing a cleavable repeating unit in the discrete PLA arms of dTSM in a sequence-specific manner, the networks could be disassembled into fragments having discrete molecular weights precisely representing their connectivity in the network. This NDS analysis confirmed that end-to-end click reactions of dTSM networks resulted in the formation of a homogeneous network above the critical concentration (∼10 w/v%) of building blocks in the solution.

Oxide Semiconductor Heterojunction Transistor with Negative Differential Transconductance for Multivalued Logic Circuits.

Multivalued logic (MVL) technology is a promising solution for improving data density and reducing power consumption in comparison to complementary metal-oxide-semiconductor (CMOS) technology. Currently, heterojunction transistors (TRs) with negative differential transconductance (NDT) characteristics, which play an important role in the function of MVL circuits, adopt organic or 2D semiconductors as active layers, but it is still difficult to apply conventional CMOS processes. Herein, we demonstrate an oxide semiconductor (OS) heterojunction TR with NDT characteristics composed of p-type copper(I) oxide (Cu2O) and n-type indium gallium zinc oxide (IGZO) using the conventional CMOS manufacturing processes. The electrical characteristics of the fabricated device exhibit a high Ion/Ioff ratio (∼3 × 103), wide NDT ranges (∼29 V), and high peak-to-valley current ratios (PVCR ≈ 25). The electrical properties of 15 devices were measured, confirming uniform performance in the PVCR, NDT range, and Ion/Ioff ratio. We analyze the device operation by varying the source/drain (S/D) position and changing the device geometry and the thickness of the Cu2O layer. Additionally, we demonstrate heterojunction ambipolar TR to elucidate the transport mechanism of NDT devices at a high gate voltage (VGS). To confirm the feasibility of the MVL circuit, we present a ternary inverter with three clearly expressed logic states that have a long intermediate state and greater margin of error induced by wide NDT regions and high PVCR.

Phytoplankton functional groups as indicators of environmental changes in weir and non-weir sections of the lower Nakdong River, Republic of Korea.

The Nakdong River underwent water impoundment after eight weirs were constructed as part of South Korea's Four Major River Restoration Project from 2009 to 2012. In this study, we aimed to confirm whether the assemblage of phytoplankton based on phytoplankton functional groups (PFGs), could indicate environmental changes in the weir section (WS) and non-weir section (NWS) of the lower Nakdong River after the construction of the weir. Thus, we examined the relationships between PFGs and gradients in environmental drivers, such as physicochemical, meteorological, and hydrological variables. Environmental gradients were observed between the WS and NWS in dissolved oxygen (DO), electric conductivity (EC), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), dissolved total nitrogen (DTN), dissolved total phosphorus (DTP), ammonia nitrogen (NH3-N), nitrate nitrogen (NO3-N), and phosphorus (PO4-P), which were relatively higher in the WS. Seventeen PFGs were identified (A, B, C, D, E, F, G, H1, J, LM, LO, MP, P, T, W1, X1, and X2). Additionally, the LM and P groups, preferring an enriched lentic system more than other groups, were found to be the dominant PFGs that led the succession of assemblages. Traditional nutrients (N, P) and organic pollutants (BOD, COD) primarily affected the autochthonous growth of the most dominant PFGs in the WS as HRT (hydraulic retention time) increased. Furthermore, the hydrological variables associated with meteorological conditions have a synergistic effect on the composition of the major PFGs and chemical and physical variables in the WS. In other words, the WS may be a new source of inoculum that primarily determines the occurrence and maintenance of phytoplankton in the immediate downstream region (NWS). In particular, group LM (mainly potentially toxic Microcystis) developing in the upper weir impoundment is transported downstream, resulting in a high inoculation effect on further growth in the NWS during the summer monsoon season.

Optimization of process parameters in micro-scale pneumatic aerosol jet printing for high-yield precise electrodes.

Aerosol jet printing (AJP) is a new non-contact direct writing technique designed to achieve precise and intricate patterns on various substrates. Specifically, the pneumatic AJP process breaks down the ink into fine particles, significantly reducing the risk of nozzle clogging and rendering it highly advantageous for industrial applications. This paper focuses on the optimization of the line electrode formation process using soluble silver clusters as the conductive ink, along with the aerosol formation procedure. The main parameters of the AJP process, namely sheath flow rate, atomizer flow rate, and dispensing speed, were identified and examined for their influence on line width and resistivity. Through this analysis, an operability window, including optimized conditions for printing high-quality lines using the AJP process, was established, along with a regression equation enabling the statistical estimation of line width. In summary, the outcomes of this investigation underscore the feasibility of an integrated printing system capable of precision control over line width, achieved through the optimization of AJP process parameters. Furthermore, it was established that pneumatic AJP offers robust process stability. The practical applicability of the proposed optimization techniques was assessed, highlighting their potential utilization in electrode formation processes within the electronic and display industry.

Machine Learning Driven Channel Thickness Optimization in Dual-Layer Oxide Thin-Film Transistors for Advanced Electrical Performance.

Machine learning (ML) provides temporal advantage and performance improvement in practical electronic device design by adaptive learning. Herein, Bayesian optimization (BO) is successfully applied to the design of optimal dual-layer oxide semiconductor thin film transistors (OS TFTs). This approach effectively manages the complex correlation and interdependency between two oxide semiconductor layers, resulting in the efficient design of experiment (DoE) and reducing the trial-and-error. Considering field effect mobility (𝜇) and threshold voltage (Vth ) simultaneously, the dual-layer structure designed by the BO model allows to produce OS TFTs with remarkable electrical performance while significantly saving an amount of experimental trial (only 15 data sets are required). The optimized dual-layer OS TFTs achieve the enhanced field effect mobility of 36.1 cm2  V-1  s-1 and show good stability under bias stress with negligible difference in its threshold voltage compared to conventional IGZO TFTs. Moreover, the BO algorithm is successfully customized to the individual preferences by applying the weight factors assigned to both field effect mobility (𝜇) and threshold voltage (Vth ).

The Prokaryotic Microalga Limnothrix redekei KNUA012 to Improve Aldehyde Decarbonylase Expression for Use as a Biological Resource.

The prokaryotic microalga Limnothrix redekei KNUA012 isolated from a freshwater bloom sample from Lake Hapcheon, Hapcheon-gun, South Korea, was investigated for its potential as a biofuel feedstock. Microalgae produce straight-chain alkanes/alkenes from acyl carrier protein-linked fatty acyls via aldehyde decarbonylase (AD; EC 1.2.1.3), which can convert aldehyde intermediates into various biofuel precursors, such as alkanes and free fatty acids. In L. redekei KNUA012, long-chain ADs can convert fatty aldehyde intermediates into alkanes. After heterologous AD expression in Escherichia coli (pET28-AD), we identified an AD in L. redekei KNUA012 that can synthesize various alkanes, such as pentadecane (C15H32), 8-heptadecene (C17H34), and heptadecane (C17H36). These alkanes can be directly used as fuels without transesterification. Biodiesel constituents including dodecanoic acid (C13H26O2), tetradecanoic acid (C15H30O2), 9-hexa decenoic acid (C17H32O2), palmitoleic acid (C17H32O2), hexadecanoic acid (C17H34O2), 9-octadecenoic acid (C19H36O2), and octadecanoic acid (C19H38O2) are produced by L. redekei KNUA012 as the major fatty acids. Our findings suggest that Korean domestic L. redekei KNUA012 is a promising resource for microalgae-based biofuels and biofuel feedstock.

Solvent-assisted sulfur vacancy engineering method in MoS2 for a neuromorphic synaptic memristor.

Recently, two-dimensional transition metal dichalcogenides (TMDs) such as molybdenum disulfide (MoS2) have attracted great attention due to their unique properties. To modulate the electronic properties and structure of TMDs, it is crucial to precisely control chalcogenide vacancies and several methods have already been suggested. However, they have several limitations such as plasma damage by ion bombardment. Herein, we introduced a novel solvent-assisted vacancy engineering (SAVE) method to modulate sulfur vacancies in MoS2. Considering polarity and the Hansen solubility parameter (HSP), three solvents were selected. Sulfur vacancies can be modulated by immersing MoS2 in each solvent, supported by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy analyses. The SAVE method can further expand its application in memory devices representing memristive performance and synaptic behaviors. We represented the charge transport mechanism of sulfur vacancy migration in MoS2. The non-destructive, scalable, and novel SAVE method controlling sulfur vacancies is expected to be a guideline for constructing a vacancy engineering system of TMDs.

Performance of a new auxiliary device based on wrist brace to improve accuracy and feasibility in neuromuscular monitoring with acceleromyography in prone-positioned patients undergoing lumbar spine surgery: a prospective randomized clinical trial.

Accuracy of acceleromyography (AMG) is not be comparable to that of mechanomyography or electromyography (EMG). In particular, the prone position may reduce the accuracy and feasibility of AMG. We developed a new device based on wrist brace to allow free thumb movement and fix the other parts of the hand and wrist. We aimed to test whether the brace applied to the AMG would increase precision of AMG and agreement with the EMG in the prone position. Fifty-seven patients, undergoing lumbar surgery under general anesthesia, were randomly assigned to groups to which AMG was applied with or without (no) brace (29 in group B vs. 28 in group NB). EMG was performed in the contralateral arm. Repeatability coefficients of the first twitch height (T1) and train-of-four (TOF) ratio were assessed from nine consecutive measurements during spontaneous recovery from rocuronium-induced neuromuscular block and the AMGs of the two groups were compared in prone position. The agreement between AMG and EMG in each group was assessed using the Bland-Altman method. In group B, the repeatability coefficient of T1 was significantly lower during the recovery to T1 of 25% and TOF ratio of 0.9 (P = 0.017 and 0.033, respectively), indicating higher precision. The mean differences of bias (95% limits of agreement) between AMG and EMG in TOF ratio of 0.9 were 6.839 (- 26.54 to 40.22) in group NB and 3.922 (- 21.83 to 29.67) in group B. The wide limits of agreement in group NB was slightly narrowed in group B but without significance. Trial registration: registered on the UMIN Clinical Trials Registry in August 2020 (UMIN000041310).

Analytical and Physical Investigation on Source Resistance in InxGa1-xAs Quantum-Well High-Electron-Mobility Transistors.

We present a fully analytical model and physical investigation on the source resistance (RS) in InxGa1-xAs quantum-well high-electron mobility transistors based on a three-layer TLM system. The RS model in this work was derived by solving the coupled quadratic differential equations for each current component with appropriate boundary conditions, requiring only six physical and geometrical parameters, including ohmic contact resistivity (ρc), barrier tunneling resistivity (ρbarrier), sheet resistances of the cap and channel regions (Rsh_cap and Rsh_ch), side-recessed length (Lside) and gate-to-source length (Lgs). To extract each model parameter, we fabricated two different TLM structures, such as cap-TLM and recessed-TLM. The developed RS model in this work was in excellent agreement with the RS values measured from the two TLM devices and previously reported short-Lg HEMT devices. The findings in this work revealed that barrier tunneling resistivity already played a critical role in reducing the value of RS in state-of-the-art HEMTs. Unless the barrier tunneling resistivity is reduced considerably, innovative engineering on the ohmic contact characteristics and gate-to-source spacing would only marginally improve the device performance.

Effect of surgical pleth index-guided remifentanil administration on perioperative outcomes in elderly patients: a prospective randomized controlled trial.

BACKGROUND: During general anesthesia, the surgical pleth index (SPI) monitors nociception. The evidence of SPI in the elderly remains scarce. We aimed to investigate whether there is a difference in perioperative outcomes following intraoperative opioid administration according to the surgical pleth index (SPI) value versus hemodynamic parameters (heart rate or blood pressure) in elderly patients. METHODS: Patients aged 65-90 years who underwent laparoscopic colorectal cancer surgery under sevoflurane/remifentanil anesthesia were randomized to receive remifentanil guided by SPI (SPI group) or conventional clinical judgment based on hemodynamic parameters (conventional group). The primary endpoint was intraoperative remifentanil consumption. Secondary endpoints were intraoperative hemodynamic instability, pain score, fentanyl consumption and delirium in the post-anesthesia care unit (PACU), and perioperative changes in interleukin-6 and natural killer (NK) cell activity. RESULTS: Seventy-five patients (38, SPI; 37, conventional) were included in the study. The SPI group consumed significantly more remifentanil intraoperatively than the conventional group (mean ± SD, 0.13 ± 0.05 vs. 0.06 ± 0.04 µg/kg/min, P < 0.001). Intraoperative hypertension and tachycardia were more common in the conventional group than in the SPI group. Pain score in the PACU (P = 0.013) and the incidence of delirium in the PACU were significantly lower in the SPI group than the conventional group (5.2% vs. 24.3%, P = 0.02). There was no significant difference in NK cell activity and interleukin-6 level. CONCLUSIONS: In the elderly patients, SPI-guided analgesia provided appropriate analgesia with sufficient intraoperative remifentanil consumption, lower incidence of hypertension/ tachycardia events, and a lower incidence of delirium in the PACU than the conventional analgesia. However, SPI-guided analgesia may not prevent perioperative immune system deterioration. TRIAL REGISTRATION: The randomized controlled trial was retrospectively registered in the UMIN Clinical Trials Registry (trial number: UMIN000048351; date of registration: 12/07/2022).

Remimazolam for General Anesthesia in a Patient with Severe Aortic Stenosis Undergoing High-Risk Surgery: A Case Report.

High-risk surgeries for patients with severe aortic stenosis (AS) are challenging for anesthesiologists and can result in hemodynamic deterioration and even mortality. We describe a case in which remimazolam was used to induce and maintain general anesthesia for a high-risk, noncardiac surgery accompanied by ongoing bleeding. An 86-year-old man with severe AS was scheduled to undergo proximal gastrectomy due to ongoing gastrointestinal bleeding and severe anemia. Remimazolam, a novel, ultra-short-acting benzodiazepine, was administered along with remifentanil for the induction and maintenance of general anesthesia. Throughout the anesthetic process, the patient's cardiac index and systemic vascular resistance were well preserved without any vasopressor support. Remimazolam seems to have possible effectiveness as a relatively safe agent for the induction and maintenance of general anesthesia in patients with severe AS who are undergoing high-risk, noncardiac surgery with bleeding.

Risk Assessment of Perioperative Respiratory Adverse Events and Validation of the COLDS Score in Children with Upper Respiratory Tract Infection.

Background and objectives: Children are at greater risk of upper respiratory tract infection (URTI), which can pose a higher risk of perioperative respiratory adverse events (PRAEs), than adults. The purpose of this study was to validate the COLDS score as a pre-anesthetic risk assessment tool for predicting the possibility of PRAEs. Materials and methods: Children aged under 18 years and undergoing elective surgery were retrospectively included. Logistic regression analysis and the area under the receiver-operating characteristic (ROC) curve (AUC) were used to estimate the ability of the COLDS score to predict PRAEs. Propensity-matched comparison was evaluated using the cut-off value from the ROC curve. Results: Among the 6252 children, 158 children had a recent URTI and 34 cases of PRAEs were reported. Age, current symptoms, and COLDS score were found to be significant variables in predicting PRAEs. From the ROC curve, values of 0.652 (p = 0.007) for AUC and 12.5 for the cut-off value of the COLDS score were calculated. Propensity-matched comparison revealed that each and every component of COLDS contributed to the higher COLDS score group. In addition to higher COLDS score, younger age and current URTI symptoms were found to be significant risk factors for PRAEs. Conclusions: This study validated the predictive power of COLDS score as a risk assessment tool for children with URTI undergoing elective surgery under general anesthesia.

Spinal Cord Injury and Postdural Puncture Headache following Cervical Interlaminar Epidural Steroid Injection: A Case Report.

Background: Cervical interlaminar epidural steroid injection (CIESI) is increasingly used as an interventional treatment for pain originating from the cervical spine. However, serious neurological complications may occur during CIESI because of direct nerve damage following inappropriate needle placement. Case report: A 35-year-old woman presented with posterior neck pain radiating to the left upper arm. Cervical magnetic resonance imaging (MRI) revealed left C6 nerve impingement. CIESI under fluoroscopic guidance was performed at another hospital using the left C5/6 interlaminar approach. Immediately after the procedure, the patient experienced dizziness, decreased blood pressure, motor weakness in the left upper arm, and sensory loss. She visited our emergency department with postdural puncture headache (PDPH) that worsened after the procedure. Post-admission cervical MRI revealed intramedullary T2 high signal intensity and cord swelling from the C4/5 to C6/7 levels; thus, a diagnosis of spinal cord injury was made. The patient's PDPH spontaneously improved after 48 h. However, despite conservative treatment with steroids, the decrease in abduction of the left fifth finger and loss of sensation in the dorsum of the left hand persisted for up to 6 months after the procedure. As noticed in the follow-up MRI performed 6 months post-procedure, the T2 high signal intensity in the left intramedullary region had decreased compared to that observed previously; however, cord swelling persisted. Furthermore, left C7/8 radiculopathy with acute denervation was confirmed by electromyography performed 6 months after the procedure. Conclusions: Fluoroscopy does not guarantee the prevention of spinal cord penetration during CIESI. Moreover, persistent neurological deficits may occur, particularly due to intrathecal perforation or drug administration during CIESI. Therefore, in accordance with the recommendations of the Multisociety Pain Workgroup, we recommend performing CIESI at the C6/7 or C7/T1 levels, where the epidural space is relatively large, rather than at the C5/6 level or higher.

RDscan: A New Method for Improving Germline and Somatic Variant Calling Based on Read Depth Distribution.

Several tools have been developed for calling variants from next-generation sequencing (NGS) data. Although they are generally accurate and reliable, most of them have room for improvement, especially regarding calling variants in datasets with low read depth. In addition, the somatic variants predicted by several somatic variant callers tend to have very low concordance rates. In this study, we developed a new method (RDscan) for improving germline and somatic variant calling in NGS data. RDscan removes misaligned reads, repositions reads, and calculates RDscore based on the read depth distribution. With RDscore, RDscan improves the precision of variant callers by removing false-positive variant calls. When we tested our new tool using the latest variant calling algorithms and data from the 1000 Genomes Project and Illumina's public datasets, accuracy was improved for most of the algorithms. After screening variants with RDscan, calling accuracies increased for germline variants in 11 of 12 cases and for somatic variants in 21 of 24 cases. RDscan is simple to use and can effectively remove false-positive variants while maintaining a low computation load. Therefore, RDscan, along with existing variant callers, should contribute to improvements in genome analysis.

Continuous Patterning of Silver Nanowire-Polyvinylpyrrolidone Composite Transparent Conductive Film by a Roll-to-Roll Selective Calendering Process.

The roll-to-roll (R2R) continuous patterning of silver nanowire-polyvinylpyrrolidone (Ag NW-PVP) composite transparent conductive film (cTCF) is demonstrated in this work by means of slot-die coating followed by selective calendering. The Ag NWs were synthesized by the polyol method, and adequately washed to leave an appropriate amount of PVP to act as a capping agent and dispersant. The as-coated Ag NW-PVP composite film had low electronic conductivity due to the lack of percolation path, which was greatly improved by the calendering process. Moreover, the dispersion of Ag NWs was analyzed with addition of PVP in terms of density and molecular weight. The excellent dispersion led to uniform distribution of Ag NWs in a cTCF. The continuous patterning was conducted using an embossed pattern roll to perform selective calendering. To evaluate the capability of the calendering process, various line widths and spacing patterns were investigated. The minimum pattern dimensions achievable were determined to be a line width of 0.1 mm and a line spacing of 1 mm. Finally, continuous patterning using selective calendering was applied to the fabrication of a flexible heater and a resistive touch sensing panel as flexible electronic devices to demonstrate its versatility.

Rapid Photoresponsive Switchable Pressure-Sensitive Adhesive Containing Azobenzene for the Mini-Light Emitting Diode Transfer Process.

Materials that can switch adhesive properties based on external stimuli are required in several industries for temporary bonding or transfer processes. Previously studied materials achieve this under restricted conditions (hydration, heat, and long switching times), and some materials have limitations related to reuse because of irreversible reactions or residue formation on substrates. Herein, a rapid photoresponsive switchable pressure-sensitive adhesive (PSA) fabricated using an acrylic polymer and an aliphatic monomer containing azobenzene is reported. The adhesion force of the proposed PSA can be switched by photoisomerizing the azobenzene moiety. The process induces the transition of surface energy and modulus of the PSA. Ultraviolet and visible light irradiation can switch the probe tack force from 200 to 4 kPa within 15-30 s. Adhesion switching is possible in a state wherein the PSA remains adhered to a substrate. Mini-LEDs are selectively transferred from the carrier PSA to a polydimethylsiloxane substrate following the process of partial adhesion switching of the PSA. The novel and switchable PSA, which exhibits a selective and repeatable adhesion switching property and high switching ratio when stimulated by light stimuli, may be potentially used to realize the mini-LED or micro-LED transfer processes.

Interaction of genetic and environmental factors for body fat mass control: observational study for lifestyle modification and genotyping.

Previous studies suggested that genetic, environmental factors and their interactions could affect body fat mass (BFM). However, studies describing these effects were performed at a single time point in a population. In this study, we investigated the interaction between genetic and environmental factors in affecting BFM and implicate the healthcare utilization of lifestyle modifications from a personalized and genomic perspective. We examined how nutritional intake or physical activity changes in the individuals affect BFM concerning the genetic composition. We conducted an observational study including 259 adult participants with single nucleotide polymorphism (SNP) genotyping and longitudinal lifestyle monitoring, including food consumption and physical activities, by following lifestyle modification guidance. The participants' lifelog data on exercise and diet were collected through a wearable device for 3 months. Moreover, we measured anthropometric and serologic markers to monitor their potential changes through lifestyle modification. We examined the influence of genetic composition on body fat reduction induced by lifestyle changes using genetic risk scores (GRSs) of three phenotypes: GRS-carbohydrate (GRS-C), GRS-fat (GRS-F), and GRS-exercise (GRS-E). Our results showed that lifestyle modifications affected BFM more significantly in the high GRS class compared to the low GRS class, indicating the role of genetic factors affecting the efficiency of the lifestyle modification-induced BFM changes. Interestingly, the influence of exercise modification in the low GRS class with active lifestyle change was lower than that in the high GRS class with inactive lifestyle change (P = 0.022), suggesting the implication of genetic factors for efficient body fat control.

ETView VivaSight single lumen vs. conventional intubation in simulated studies: a systematic review and meta-analysis.

OBJECTIVE: The ETView VivaSight single lumen airway tube (ETView) is a tracheal tube incorporating a video camera. We carried out a meta-analysis of previous simulation studies by inexperienced personnel to determine if the ETView could improve the success rate of first-attempt intubation. METHODS: We collected data from randomized controlled trials comparing the use of the ETView VivaSight single lumen versus a conventional endotracheal tube in a simulated manikin or cadaver study. RESULTS: Eleven studies (558 participants, 3,254 intubations, and 19 scenarios) were included. The ETView had a significantly higher success rate and shorter insertion time than conventional intubation in both normal airways (with or without chest compression) and in difficult airways. In addition, the ETView demonstrated better results in terms of a higher rate of Cormack-Lehane grade 1 and a lower incidence of dental trauma. CONCLUSIONS: Inexperienced personnel can insert the ETView more rapidly and with a higher intubation success rate compared with a conventional tube.

Observations of the warm-tongue circulation in the northern East China Sea.

A subsurface thermohaline front semi-permanently formed in association with near-bottom cyclonic circulation in the northern East China Sea was newly found from detailed hydrographic data collected during two cruises in February 2017 (winter) and April 2018 (spring) along with supplementary satellite remote sensing and historical hydrographic data. An alternate intruding frontal structure in water properties was observed across the cyclonic circulation in both seasons as formed by two contrasting water masses-low-temperature and low-salinity (i.e., low spiciness) water transported by the East China Sea Current and high-temperature and high-salinity (i.e., high spiciness) water transported by the Tsushima Warm Current. Consistent structures were confirmed from current observations during the two cruises, historical hydrographic observations, and satellite altimetry-derived sea surface height and surface frontal structure, indicative of retroflection of the Cheju Warm Current as deemed by the seasonal development of thermal stratification in spring. Our results reveal significant heat and material exchanges between the open Pacific and the broad shelf, particularly via diapycnal mixing and cross-front transports associated with across-front flow and cyclonic circulation, in the northern East China Sea.