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Background: Limited data exist regarding ventilation in patients with class III obesity [body mass index (BMI) > 40 kg/m2] and acute respiratory distress syndrome (ARDS). The aim of the present study was to determine whether an individualized titration of mechanical ventilation according to cardiopulmonary physiology reduces the mortality in patients with class III obesity and ARDS. Methods: In this retrospective study, we enrolled adults admitted to the ICU from 2012 to 2017 who had class III obesity and ARDS and received mechanical ventilation for > 48 h. Enrolled patients were divided in two cohorts: one cohort (2012-2014) had ventilator settings determined by the ARDSnet table for lower positive end-expiratory pressure/higher inspiratory fraction of oxygen (standard protocol-based cohort); the other cohort (2015-2017) had ventilator settings determined by an individualized protocol established by a lung rescue team (lung rescue team cohort). The lung rescue team used lung recruitment maneuvers, esophageal manometry, and hemodynamic monitoring. Results: The standard protocol-based cohort included 70 patients (BMI = 49 ± 9 kg/m2), and the lung rescue team cohort included 50 patients (BMI = 54 ± 13 kg/m2). Patients in the standard protocol-based cohort compared to lung rescue team cohort had almost double the risk of dying at 28 days [31% versus 16%, P = 0.012; hazard ratio (HR) 0.32; 95% confidence interval (CI95%) 0.13-0.78] and 3 months (41% versus 22%, P = 0.006; HR 0.35; CI95% 0.16-0.74), and this effect persisted at 6 months and 1 year (incidence of death unchanged 41% versus 22%, P = 0.006; HR 0.35; CI95% 0.16-0.74). Conclusion: Individualized titration of mechanical ventilation by a lung rescue team was associated with decreased mortality compared to use of an ARDSnet table.

The MOS technology using high-k dielectrics on high carrier mobility semiconductors of InGaAs leading to a faster speed at lower power is now at the International Technology Roadmap for Semiconductors (ITRS). Great efforts have been dedicated to understand the high k/InGaAs interface. This project involves an examination of interfacial electronic structure of in-situ HfO2 on In0.53Ga0.47As\(001)-4x2 probed by synchrotron radiation photoemission. The dielectric film was prepared by atomic layer deposition (ALD) with the precursors as tetrakis[ethylmethylamino] Hafnium (TEMAHf) and water. Samples were kept under ultra-high-vacuum (UHV) throughout from MBE/ALD preparation to data-acquisition photoemission chambers in the synchrotronradiation facility. The high-resolution work with a short inelastic mean-free path allowed for the first time identification of atom-toatom interaction at this interface. This work has elucidated the mechanism and nature of the bonding between the Hf atom in TEMAHf and In/As atoms of the reconstructed In0.53Ga0.47As(001)-4x2 surface. The TEMAHf precursor is either intact, or loses one ethylmethylamino ligand to become tri-EMAHf. The initial purge of the TEMAHf precursors effectively passivates all the edge As atoms in the top row. As a result, no oxygen bonding was found at either surface As or In atoms. The subsequent water purge reacts with tri-EMAHf to facilitate the growth of hafnium oxides there. The interface obtained by ALD in the present study found no evidence of oxygen bonding to any atom in the trough. The unpassivated surface In atoms may contribute to the frequency dispersion in the accumulation region of n-In0.53Ga0.47As MOSCAP.

Our research activities during the last eight years from 2006 to 2013, with the grant supports from Nano National programs, NSC, Taiwan and AOARD, have been pushing the material limits of III-V InGaAs and GaN metal-oxide-semiconductor (MOS) systems using high-k dielectrics. In the third year of the funding, with the capabilities of atomic-scale probing and manipulating the high-k oxides/semiconductors interfaces, we have established the correlations between electronic structures and electrical properties essential to understand the Fermi level pinning/unpinning mechanism of the interfaces between metal/oxide and oxide/semiconductor. we have successfully continuously kept our world-leading expertise of high-k dielectric growth on InGaAs by achieving world record drain current of 1.8 mA/micro m, transconductance of 0.80 mS/micro m, and low sub-thresholds in a self-aligned inversion-channel InGaAs metal-oxide-semiconductor field-effect- transistor of 1 micro m gate length. In-situ ultrahigh vacuum deposited Y2O3 and HfO2 and atomic-layer-deposited (ALD) Al2O3 and HfO2 2-3 mono-layers thick on freshly grown In0.53Ga0.47As, with an Al2O3 cap, were employed as a gate dielectric., Prepared in collaboration with the Department of Physics, National Tsing Hua University, Hsinchu, Taiwan, Republic of China.

This is the final report of a project in which chemical and electronic characteristics on Al2O3/Gd2O3/InAs interfaces were studied using x-ray photoelectron spectroscopy.

This is the final report of a project to understand the mechanism of surface Fermi level pinning/unpinning in InAs and GaSb, and further effectively passivate them using high dielectrics.

This is the report of a project to grow high dielectric constant oxides on InGaAs and GaN using molecular beam epitaxy and atomic layer deposition., Prepared in cooperation with National Taiwan University, Taipei, Taiwan.

Magnetic properties of Fe3Si films with thickness from 2 to 210 monolayers (ML) epitaxially grown on GaAs (001) were studied using a superconducting quantum interference device and alternating gradient force magnetometers. Growth of these single-crystal intermetallic compound films were carried out in a multichamber molecular beam epitaxy (MBE) system. The samples were covered in situ with Au 50 Å thick to prevent oxidation when the samples were removed from the MBE chamber. All the films are ferromagnetic even for samples as thin as 2 ML. The easy magnetization direction of the films is parallel to the film surface. The magnetic coercivity forces (Hc) of the samples increase as the film thickness decreases to 10 ML, and then decrease when the film thickness decreases further to 2 ML.

A combined x-ray photoemission and diamagnetic-susceptibility study of YBa2Cu3Ox with x≃6 and 7 has been performed, with emphasis on the oxygen defect and the effect of heating in vacuum. By comparing spectra taken at these two oxygen contents, the core levels observed in the O 1s and Ba 4d spectral range are identified. Peak-intensity analysis indicates (1) that the oxygen released during the in situ heating is derived from or near the Cu-O-Cu-O chains of YBa2Cu3O7 and (2) that there is a random distribution of oxygen defects in or near these chains leading to two chemically dissimilar barium atoms even in single-orthorhombic-phase samples.

Interband and core-level transitions and plasmon resonance in the high-temperature oxide superconductor YBa2Cu3O7-x were studied by transmission electron-energy-loss spectroscopy using an electron microprobe ∼5-10 Å in size. Both single-crystal and polycrystalline ceramic samples have been examined. No significant change in electronic structure was observed at the grain boundaries. A 13.5-eV interband-transition peak was found to be sensitive to damages created by ion-beam bombardment.

Superconducting Y1Ba2Cu3O7-x films were produced by metal molecular-beam epitaxy with one electron beam and two thermal cells and a molecular oxygen-gas source. The films were epitaxially grown on SrTiO3 (100) with an a-axis orientation perpendicular to the plane, and b and c axes ordered in the plane. A sharp resistive superconducting transition with Tc (R=0) at 82 K was obtained. A lower limit of the average Jc in the plane is 103 A/cm2 at 77 K, 5×104 A/cm2 at 70 K, and 106 A/cm2 at 4.2 K.

We compare the superlattice modulation, microstructure, and epitaxy of Tl2Ba2Ca2Cu3O10 thin films grown on MgO [100] and SrTiO3 [100] substrates by dc diode sputtering. Films grown on MgO were found to be quite clean with the c axis perpendicular to the substrate. However, no in-plane orientational relationship to the substrate was found. Films grown on SrTiO3, on the other hand, showed very good epitaxy to the substrate despite the presence of second phases. Films grown on MgO also exhibited a longer coherence length of the superlattice modulation than those grown on SrTiO3 under identical conditions.

We have prepared superconducting thin films of Y-Ba-Cu-O with Tc onsets above 95 K by both diode and magnetron sputtering. Films with full superconductivity (R=0) at 85 K have been produced by dc magnetron sputtering. The compositions of the films are fairly uniform across an area 50 mm in diameter and through the film thickness. Structural properties of the films were studied by x-ray diffraction. Critical current densities in the range of 3000 to 104 A/cm2 have been measured at 4.2 K. Applied Physics Letters is copyrighted by The American Institute of Physics.

A new technique for producing thin films of the high-temperature perovskite superconductors, LnBa2Cu3O7-x, where Ln represents a rare-earth element, using spin-on metalorganic precursors is described. Pyrolysis of the spin-coated films, consisting of mixed metal (2-ethyl hexanoates), leads to black films up to several microns thick whose degree of orientation is a function of the processing temperature and duration. Representative films of Y Ba2Cu3O7-x on MgO begin to exhibit orientation with the c axis perpendicular to the film plane at heat treatments above 900 °C. The superconducting behavior of a highly oriented film produced at 990 °C is characterized by Tc(onset)=89 K, Tc(R=0)=77 K, and Jc=103 A cm-2 at 65 K.

Superconducting Tl-Ba-Ca-Cu-O thin films 0.2–1.0 µm thick have been prepared on MgO(100) and SrTiO3 (100) substrates by dc diode sputtering using a single oxide target. Films containing primarily the Tl2Ba2Ca1Cu2O8 phase were obtained with a Tc (R =0) at 102 K and a transport Jc of 104 A/cm2 at 90 K. For the nearly pure phase Tl2Ba2Ca2Cu3O10 films, the Tc's (R =0) are higher at 116 K and the transport Jc's at 100 K are of 105 A/cm2. Both types of films show a strong preferred orientation with the c axis perpendicular to the film plane. The rocking curve of the Tl2Ba2Ca2Cu3O10 films is 0.32° wide and the typical grain size is over 10 µm.

High Tc superconducting Y-Ba-Cu-O films have been produced by rf magnetron sputtering using single unreacted composite targets of Y2O3, BaF2, and CuO powders. Transport measurements of the films showed a sharp resistive Tc (R=0) at 89 K and a metallic behavior of resistivity versus temperature. The films show preferred orientations when deposited on single-crystal SrTiO3 substrates (100) or (110) and followed by a post O2 annealing at 825 °C.