Enhancing Si3N4 Selectivity over SiO2 in Low-RF Power NF3-O2 Reactive Ion Etching: The Effect of NO Surface Reaction.

Highly selective etching of silicon nitride (Si3N4) and silicon dioxide (SiO2) has received considerable attention from the semiconductor community owing to its precise patterning and cost efficiency. We investigated the etching selectivity of Si3N4 and SiO2 in an NF3/O2 radio-frequency glow discharge. The etch rate linearly depended on the source and bias powers, whereas the etch selectivity was affected by the power and ratio of the gas mixture. We found that the selectivity can be controlled by lowering the power with a suitable gas ratio, which affects the surface reaction during the etching process. X-ray photoelectron spectroscopy of the Si3N4 and QMS measurements support the effect of surface reaction on the selectivity change by surface oxidation and nitrogen reduction with the increasing flow of O2. We suggest that the creation of SiOxNy bonds on the surface by NO oxidation is the key mechanism to change the etch selectivity of Si3N4 over SiO2.

Development of the Tele-Measurement of Plasma Uniformity via Surface Wave Information (TUSI) Probe for Non-Invasive In-Situ Monitoring of Electron Density Uniformity in Plasma Display Fabrication Process.

The importance of monitoring the electron density uniformity of plasma has attracted significant attention in material processing, with the goal of improving production yield. This paper presents a non-invasive microwave probe for in-situ monitoring electron density uniformity, called the Tele-measurement of plasma Uniformity via Surface wave Information (TUSI) probe. The TUSI probe consists of eight non-invasive antennae and each antenna estimates electron density above the antenna by measuring the surface wave resonance frequency in a reflection microwave frequency spectrum (S11). The estimated densities provide electron density uniformity. For demonstration, we compared it with the precise microwave probe and results revealed that the TUSI probe can monitor plasma uniformity. Furthermore, we demonstrated the operation of the TUSI probe beneath a quartz or wafer. In conclusion, the demonstration results indicated that the TUSI probe can be used as an instrument for a non-invasive in-situ method for measuring electron density uniformity.

Psychological scales as predictors of emergency department hospitalizations in suicide attempters.

BACKGROUND: The purpose of this study was to evaluate the psychological scales reflecting lethality and intent as predictors of suicide attempter's hospitalization. METHODS: Data of suicide attempters aged over 15years, who visited the ED from January 2013 to June 2016, were retrospectively collected and they were divided into the hospitalization and discharge groups. We evaluated the Risk-Rescue Rating Scale (RRRS) and Self-Inflicted Injury Severity Form (SIISF) for lethality and Suicide Intent Scale (SIS) for intent, respectively. The predictive abilities of these scales for hospitalization were compared in terms of performance (AUCs) and goodness-of-fit (the Bayesian information criterion [BIC]). RESULTS: A total of 382 suicide attempters were enrolled, of which 233 (61%) were hospitalized. The scores of all psychological scales were significantly higher in the hospitalization group and all scales were identified as independent predictors of hospitalization. The AUC of the RRRS tended to be higher than those of the SIS and SIISF; similarly, the RRRS demonstrated the best overall fit (the lowest BIC). The AUC of combined the RRRS and SIS was superior to that of any of the individual scales alone. While the AUC of combined the SIISF and SIS was superior to that of either individual scale, it was comparable to that of the RRRS. CONCLUSIONS: The psychological scales can be helpful for predicting suicide attempter's hospitalization in emergency settings. Especially, the RRRS seemed to have a superior predictive ability. Moreover, combining the scales had significantly better predictive performance than use of the individual scale alone did.

Proton beam therapy reduces the incidence of acute haematological and gastrointestinal toxicities associated with craniospinal irradiation in pediatric brain tumors.

BACKGROUND: The benefits of proton beam craniospinal irradiation (PrBCSI) in children have been extensively reported in dosimetric studies. However, there is limited clinical evidence supporting the use of PrBCSI. We compared the acute toxicity of PrBCSI relative to that of conventional photon beam CSI (PhBCSI) in children with brain tumours. MATERIAL AND METHODS: We prospectively evaluated the haematological and gastrointestinal toxicities in 30 patients who underwent PrBCSI between April 2008 and December 2012. As a reference group, we retrospectively evaluated the medical records of 13 patients who underwent PhBCSI between April 2003 and April 2012. The median follow-up time from starting CSI was 22 months (range 2-118 months). The mean irradiation dose was 32.1 Gy (range 23.4-39.6 Gy) and 29.4 CGE (cobalt grey equivalents; range 19.8-39.6), in the PrBCSI and PhBCSI groups, respectively (p = 0.236). RESULTS: There was no craniospinal fluid space relapse after curative therapy in either group of patients. Thrombocytopenia was less severe in the PrBCSI group than in the PhBCSI group (p = 0.012). The recovery rates of leukocyte and platelet counts measured one month after treatment were significantly greater in the PrBCSI group than in the PhBCSI group (p = 0.003 and p = 0.010, respectively). Diarrhoea was reported by 23% of patients in the PhBCSI group versus none in the PrBCSI group (p = 0.023). CONCLUSIONS: The incidence rates of thrombocytopenia and diarrhoea were lower in the PrBCSI group than in the PhBCSI group. One month after completing treatment, the recovery from leukopenia and thrombocytopenia was better in patients treated with PrBCSI than in those treated with PhBCSI.

Crystal structure of di-chlorido-{2-[(2-hy-droxyeth-yl)(pyridin-2-ylmeth-yl)amino]-ethano-lato-κ(4) N,N',O,O'}iron(III) dihydrate from synchrotron data.

In the title compound, [Fe(C10H15N2O2)Cl2]·2H2O, the Fe(III) ion is coordinated by two N and two O atoms of the tetra-dentate 2-{(2-hy-droxy-eth-yl)(pyridin-2-ylmeth-yl)amino}-ethano-late ligand and by two chloride anions, resulting in a distorted octa-hedral coordination sphere. The average Fe-X (X = ligand N and O atoms) and Fe-Cl bond lengths are 2.10 and 2.32 Å, respectively. In the crystal, duplex O-H⋯O hydrogen bonds between the hydroxyl and eth-oxy groups of two neighbouring complexes give rise to a dimeric unit. The dimers are connected to the lattice water mol-ecules (one of which is equally disordered over two sets of sites) through O-H⋯Cl hydrogen bonds, forming undulating sheets parallel to (010). Weak C-H⋯Cl hydrogen bonds are also observed.

Energy-Based Unified Models for Predicting the Fatigue Life Behaviors of Austenitic Steels and Welded Joints in Ultra-Supercritical Power Plants.

The development of a cost-effective and accurate model for predicting the fatigue life of materials is essential for designing thermal power plants and assessing their structural reliability under operational conditions. This paper reports a novel energy-based approach for developing unified models that predict the fatigue life of boiler tube materials in ultra-supercritical (USC) power plants. The proposed method combines the Masing behavior with a cyclic stress-strain relationship and existing stress-based or strain-based fatigue life prediction models. Notably, the developed models conform to the structure of the modified Morrow model, which incorporates material toughness (a temperature compensation parameter) into the Morrow model to account for the effects of temperature. A significant advantage of this approach is that it eliminates the need for tensile tests, which are otherwise essential for assessing material toughness in the modified Morrow model. Instead, all material constants in our models are derived solely from fatigue test results. We validate our models using fatigue data from three promising USC boiler tube materials-Super304H, TP310HCbN, and TP347H-and their welded joints at operating temperatures of 500, 600, and 700 °C. The results demonstrate that approximately 91% of the fatigue data for all six materials fall within a 2.5× scatter band of the model's predictions, indicating a high level of accuracy and broad applicability across various USC boiler tube materials and their welded joints, which is equivalent to the performance of the modified Morrow model.

Correlation between Cellular Structure Morphology and Anisotropic Yield in Additively Manufactured Stainless Steel 316L.

Additively manufactured austenitic stainless steel 316L is composed of a cellular structure, which has a directionality, and is observed with a different morphology depending on the observation direction. The cellular structure morphology that appears with a high probability in grains with a specific grain orientation is determined. Taylor factor, which is calculated by considering grain orientation, is related to cellular structure morphology due to the directional cellular structure in additively manufactured austenitic stainless steel 316L. The Taylor factor affects the mechanical properties. The yield strength of additively manufactured SUS316L can be explained by the correlation between cellular structure morphology, grain orientation, and Taylor factor.

Is the dislocation rate higher after bipolar hemiarthroplasty in patients with neuromuscular diseases?

BACKGROUND: Patients with neuromuscular disease reportedly have a higher incidence of postoperative dislocation after bipolar hemiarthroplasty. Although the literature has focused on a high prevalence of preoperative neurologic conditions in patients who had dislocations after bipolar hemiarthroplasties, the relative incidence of dislocation in patients with neuromuscular disease and without is unclear. QUESTIONS/PURPOSES: We therefore (1) asked whether the incidence of postoperative dislocation after bipolar hemiarthroplasty was greater in patients with neuromuscular disease than for those without, and (2) whether function differed between the two groups, and (3) explored potential risk factors for dislocation in two groups. METHODS: We retrospectively reviewed 190 patients who underwent bipolar hemiarthroplasties for fracture of the femoral neck between 1996 and 2008. Of the 190 patients, 42 had various neuromuscular diseases and 148 had no history of neuromuscular disease. Intraoperative stability was tested and posterior soft tissue repair was performed in all patients. We determined the incidence of dislocation, postoperative leg length discrepancy, and femoral offset in patients with or without neuromuscular disease. RESULTS: The incidence of dislocation was 2.6% in all patients. We observed similar rates of dislocation in the two groups: 4.8% (two of 42 hips) in patients with neuromuscular disease and 2.0% (three of 148 hips) in patients without neuromuscular disease. CONCLUSIONS: In femoral neck fractures in patients with neuromuscular disease, careful preoperative management and operative technique such as a posterior soft tissue repair might decrease the risk of postoperative dislocation; therefore, we consider the bipolar hemiarthroplasty a reasonable treatment option. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Black Si Photocathode with a Conformal and Amorphous MoSx Catalytic Layer Grown Using Atomic Layer Deposition for Photoelectrochemical Hydrogen Evolution.

We demonstrated how the photoelectrochemical (PEC) performance was enhanced by conformal deposition of an amorphous molybdenum sulfide (a-MoSx) thin film on a nanostructured surface of black Si using atomic layer deposition (ALD). The a-MoSx is found to predominantly consist of an octahedral structure (S-deficient metallic phase) that exhibits high electrocatalytic activity for the hydrogen evolution reaction with a Tafel slope of 41 mV/dec in an acid electrolyte. The a-MoSx has a smaller work function (4.0 eV) than that of crystalline 2H-MoS2 (4.5 eV), which induces larger energy band bending at the p-Si surface, thereby facilitating interface charge transfer. These features enabled us to achieve an outstanding kinetic overpotential of ∼0.2 V at 10 mA/cm2 and an onset potential of 0.27 V at 1 mA/cm2. Furthermore, the a-MoSx layer provides superior protection against corrosion of the Si surface, enabling long-term PEC operation of more than 50 h while maintaining 87% or more performance. This work highlights the remarkable advantages of the ALD a-MoSx layer and leads to a breakthrough in the architectural design of PEC cells to ensure both high performance and stability.

Observation of prior light emission before arcing development in a low-temperature plasma with multiple snapshot analysis.

Arcing is a ubiquitous phenomenon and a crucial issue in high-voltage applied systems, especially low-temperature plasma (LTP) engineering. Although arcing in LTPs has attracted interest due to the severe damage it can cause, its underlying mechanism has yet to be fully understood. To elucidate the arcing mechanism, this study investigated various signals conventionally used to analyze arcing such as light emission, arcing current and voltage, and background plasma potential. As a result, we found that light emission occurs as early as 0.56 µs before arcing current initiation, which is a significant indicator of the explosive development of arcing as well as other signals. We introduce an arcing inducing probe (AIP) designed to localize arcing on the tip edge along with multiple snapshot analysis since arcing occurs randomly in space and time. Analysis reveals that the prior light emission consists of sheath and tip glows from the whole AIP sheath and the AIP tip edge, respectively. Formation mechanisms of these emissions based on multiple snapshot image analysis are discussed. This light emission before arcing current initiation provides a significant clue to understanding the arcing formation mechanism and represents a new indicator for forecasting arcing in LTPs.

Shear band-driven precipitate dispersion for ultrastrong ductile medium-entropy alloys.

Precipitation strengthening has been the basis of physical metallurgy since more than 100 years owing to its excellent strengthening effects. This approach generally employs coherent and nano-sized precipitates, as incoherent precipitates energetically become coarse due to their incompatibility with matrix and provide a negligible strengthening effect or even cause brittleness. Here we propose a shear band-driven dispersion of nano-sized and semicoherent precipitates, which show significant strengthening effects. We add aluminum to a model CoNiV medium-entropy alloy with a face-centered cubic structure to form the L21 Heusler phase with an ordered body-centered cubic structure, as predicted by ab initio calculations. Micro-shear bands act as heterogeneous nucleation sites and generate finely dispersed intragranular precipitates with a semicoherent interface, which leads to a remarkable strength-ductility balance. This work suggests that the structurally dissimilar precipitates, which are generally avoided in conventional alloys, can be a useful design concept in developing high-strength ductile structural materials.

EGR1/GADD45α Activation by ROS of Non-Thermal Plasma Mediates Cell Death in Thyroid Carcinoma.

(1) Background: Nonthermal plasma (NTP) induces cell death in various types of cancer cells, providing a promising alternative treatment strategy. Although recent studies have identified new mechanisms of NTP in several cancers, the molecular mechanisms underlying its therapeutic effect on thyroid cancer (THCA) have not been elucidated. (2) Methods: To investigate the mechanism of NTP-induced cell death, THCA cell lines were treated with NTP-activated medium -(NTPAM), and gene expression profiles were evaluated using RNA sequencing. (3) Results: NTPAM upregulated the gene expression of early growth response 1 (EGR1). NTPAM-induced THCA cell death was enhanced by EGR1 overexpression, whereas EGR1 small interfering RNA had the opposite effect. NTPAM-derived reactive oxygen species (ROS) affected EGR1 expression and apoptotic cell death in THCA. NTPAM also induced the gene expression of growth arrest and regulation of DNA damage-inducible 45α (GADD45A) gene, and EGR1 regulated GADD45A through direct binding to its promoter. In xenograft in vivo tumor models, NTPAM inhibited tumor progression of THCA by increasing EGR1 levels. (4) Conclusions: Our findings suggest that NTPAM induces apoptotic cell death in THCA through a novel mechanism by which NTPAM-induced ROS activates EGR1/GADD45α signaling. Furthermore, our data provide evidence that the regulation of the EGR1/GADD45α axis can be a novel strategy for the treatment of THCA.

Head and Neck Cancer Cell Death due to Mitochondrial Damage Induced by Reactive Oxygen Species from Nonthermal Plasma-Activated Media: Based on Transcriptomic Analysis.

Mitochondrial targeted therapy is a next-generation therapeutic approach for cancer that is refractory to conventional treatments. Mitochondrial damage caused by the excessive accumulation of reactive oxygen species (ROS) is a principle of mitochondrial targeted therapy. ROS in nonthermal plasma-activated media (NTPAM) are known to mediate anticancer effects in various cancers including head and neck cancer (HNC). However, the signaling mechanism of HNC cell death via NTPAM-induced ROS has not been fully elucidated. This study evaluated the anticancer effects of NTPAM in HNC and investigated the mechanism using transcriptomic analysis. The viability of HNC cells decreased after NTPAM treatment due to enhanced apoptosis. A human fibroblast cell line and three HNC cell lines were profiled by RNA sequencing. In total, 1 610 differentially expressed genes were identified. Pathway analysis showed that activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP) were upstream regulators. Mitochondrial damage was induced by NTPAM, which was associated with enhancements of mitochondrial ROS (mtROS) and ATF4/CHOP regulation. These results suggest that NTPAM induces HNC cell death through the upregulation of ATF4/CHOP activity by damaging mitochondria via excessive mtROS accumulation, similar to mitochondrial targeted therapy.

Effects of finish rolling temperature and yield ratio on variations in yield strength after pipe-forming of API-X65 line-pipe steels.

Flattened plates often show the lower or higher yield strength than initial leveled plates because tensile and compressive strains are repeatedly experienced at outer and inner walls during the pipe-forming and flattening, but reasons for the yield-strength variation after the pipe-forming are not sufficiently verified yet. In this study, ten line-pipe steels were fabricated by controlling alloying elements and finish rolling temperatures (FRTs), and the yield strength of pipe-flattened steel plates was predicted by using cyclic simulation tests, based on competing contributions of Bauschinger effect (BE) and strain hardening (SH) effect quantified from yield drop (YD) and yield rise (YR) parameters, respectively. High-FRT-treated steels (H steels) showed the lower BE and the higher SH than low-FRT-treated steels (L steels), thereby resulting in the smaller yield-strength reduction. This lower BE in the H steels was caused by the lower total boundary density, while the higher SH was caused by the higher fraction of granular bainite. According to the SH analyses between the YR parameters obtained from cyclic simulation tests and the yield ratios obtained from ordinary tensile tests, the decrease in yield-strength reduction with decreasing yield ratio was not attributed to the increase in ordinary tensile SH but to the increase in YR parameter.

Solvent-triggered single-crystal-to-single-crystal transformation from a monomeric to polymeric copper(II) complex based on an aza macrocyclic ligand.

Reversible solvent-triggered single-crystal-to-single-crystal (SCSC) transformations are observed between two copper(II) azamacrocyclic complexes: [Cu(C16H38N6)(H2O)2](C12H6O4) (1) and [Cu(C16H38N6)(C12H6O4)] (2). Complex (1) was prepared via self-assembly of a copper(II) azamacrocyclic complex containing butyl pendant groups, [Cu(C16H38N6)(ClO4)2], with 2,7-naphthalenedicarboxylic acid. When monomeric compound (1) was immersed in CH3OH, coordination polymer (2) was obtained, indicating a solvent-triggered SCSC transformation. Furthermore, when (2) was immersed in water, an reverse SCSC transformation from (2) to (1) occurred. Complex (1) presents a 3D supramolecular structure formed via intermolecular hydrogen-bonding interactions, whereas complex (2) features a 1D zigzag coordination polymer. The reversible SCSC transformation of (1) and (2) was characterized using single-crystal X-ray diffraction and in situ powder X-ray diffraction techniques. Despite its poor porosity, complex (2) displayed interesting CO2 adsorption behaviour under CO2 gas.

Bipolar Energetics and Bifunctional Catalytic Activity of a Nanocrystalline Ru Thin-Film Enable High-Performance Photoelectrochemical Water Reduction and Oxidation.

Photoelectrochemical (PEC) cells, which represent a promising technology for the production of hydrogen fuel through water splitting reactions, must meet two criteria to achieve high-performance operation: (i) a high thermodynamic open-circuit potential and (ii) a low kinetic overpotential. Herein, we achieved these criteria in both an oxygen-evolving n-Si photoanode and hydrogen-evolving p-Si photocathode by simple electrodeposition of a nanocrystalline thin film of Ru. The bifunctional electrocatalytic activity of the nanocrystalline Ru led to low overpotentials in both the acidic oxygen evolution reaction (0.27 V) and alkaline hydrogen evolution reaction (0.04 V). In addition, the nanocrystalline Ru/Si junctions influenced the interface energetics via the induction of an extrinsic electrochemical potential on the surface of the Ru nanocrystals through a redox reaction rather than the chemical potential of the electrons (work function) of bulk Ru. The nanocrystalline Ru film exhibited bipolar applicability, enabling both Ru/n-Si and Ru/p-Si junctions with high Voc values of 0.63 and 0.5 V, respectively. As a result, the n-Si photoanode in the acidic electrolyte and the p-Si photocathode in the alkaline electrolyte generated a photocurrent of 10 mA/cm2 at record values of 0.87 and 0.42 V versus the reversible hydrogen electrode, respectively. These results provide insight into the development of high-performance PEC cells based on a nanocrystalline electrocatalyst.

Dosimetric comparison of four different external beam partial breast irradiation techniques: three-dimensional conformal radiotherapy, intensity-modulated radiotherapy, helical tomotherapy, and proton beam therapy.

BACKGROUND AND PURPOSE: As an alternative to whole breast irradiation in early breast cancer, a variety of accelerated partial breast irradiation (APBI) techniques have been investigated. The purpose of our study is to compare the dosimetry of four different external beam APBI (EB-APBI) plans: three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), helical tomotherapy (TOMO), and proton beam therapy (PBT). METHODS AND MATERIALS: Thirty patients were included in the study, and plans for four techniques were developed for each patient. A total dose of 30Gy in 6Gy fractions once daily was prescribed in all treatment plans. RESULTS: In the analysis of the non-PTV breast volume that was delivered 50% of the prescribed dose (PD), PBT (mean: 16.5%) was superior to TOMO (mean: 22.8%), IMRT (mean: 33.3%), and 3D-CRT (mean: 40.9%) (p<0.001). The average ipsilateral lung volume percentage receiving 20% of the PD was significantly lower in PBT (0.4%) and IMRT (2.3%) compared with 3D-CRT (6.0%) and TOMO (14.2%) (p<0.001). The average heart volume percentage receiving 20% and 10% of the PD in left-sided breast cancer (N=19) was significantly larger with TOMO (8.0%, 19.4%) compared to 3D-CRT (1.5%, 3.1%), IMRT (1.2%, 4.0%), and PBT (0%, 0%) (p<0.001). CONCLUSIONS: All four EB-APBI techniques showed acceptable coverage of the PTV. However, effective non-PTV breast sparing was achieved at the cost of considerable dose exposure to the lung and heart in TOMO.

Crystal structure of {2-methyl-2-[(pyridin-2-yl-meth-yl)amino]-propan-1-ol-κ3 N,N',O}bis-(nitrato-κO)copper(II) from synchrotron data.

The title compound, [Cu(NO3)2(C10H16N2O)], has been synthesized and characterized by synchrotron single-crystal diffraction at 100 K. The CuII ion has a distorted square-pyramidal coordination geometry with two N and one O atoms of the C10H16N2O ligand and one nitrate anion in the equatorial plane and another nitrate anion at the axial position. The equatorial Cu-N and Cu-O bond lengths are in the range 1.9608 (14)-2.0861 (15) Å, which are shorter than the axial Cu-Onitrate bond length [2.1259 (16) Å]. In the crystal, mol-ecules are linked via inter-molecular N-H⋯O and O-H⋯O hydrogen bonds, forming a sheet structure parallel to the bc plane. The sheets are further linked through a face-to-face π-π inter-action [centroid-centroid distance = 3.994 (1) Å]. Weak inter-molecular C-H⋯O inter-actions are also observed in the sheet and between adjacent sheets.

Yield-strength prediction of flattened steel pipes by competing Bauschinger effect and strain hardening during pipe-forming.

Since flattened steel sheets often show the unexpectedly lower or higher yield strength than leveled sheets, unceasing efforts have been made to accurately predict the yield strength in pipe-forming industries. In the present investigation, the yield strength of line-pipe or casing-pipe steels was predicted by competing Bauschinger effect and strain hardening occurred during the pipe-forming. Yield drop (YD) and yield rise (YR) parameters were newly defined from cyclic simulation analyses of outer and inner walls of pipes to express more reasonably the Bauschinger effect and strain hardening. The YD increased abruptly until the pre-strain of about 1%, and then saturated, while the YR increased linearly with increasing pre-strain. By combining the YD and YR, the variation in yield strength (Δσ) showed a down-and-up behavior as the Bauschinger effect and strain hardening were dominant at low and high pre-strains, respectively, and plausibly explained the relationship of Δσ and piping strain used in pipe-forming industries. According to the microstructural analyses related to the down-and-up Δσ behavior, the polygonal ferrite reduced the yield-strength reduction in the low pre-strain range, whereas the granular bainite or pearlite expanded it. This yield strength prediction coupled with microstructural analyses provide a good idea for designing and reliably predicting the yield strength of in various steel pipes.