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The cyclic thermal process can assist and accelerate the kinetics of phase transformation. Conventional UNS S17400 grade stainless is characterized by a martensitic microstructure. After solution treatment, the steel was aged by thermal cycling between 600 °C and 25 °C and quenched in water in each cycle, completing under the self-designed system. The nano precipitates of very fine copper particles and larger NbC particles were found by using transmission electron microscopy (TEM). The fraction and quantity of high angle grain boundaries (HAGBs) after 36 cycles were the highest among the three numbers of thermal cycles. The peak hardness also occurred after 36 cycles and was attributed to the finest grains, high fraction of HAGBs, and the largest local microstrain. The microtwins and the reverted γ were formed by the thermal cycling process. The estimated fraction value of reverted γ was very low, below 0.1, with a calculated precipitation rate about 12.6 s−1 at t0.5.

Abstract Heparin-binding protein (HBP) has been shown to be a robust predictor of the progression to organ dysfunction from sepsis, and we hypothesized that dynamic changes in HBP may reflect the severity of sepsis. We therefore aim to investigate the predictive value of baseline HBP, 24-h, and 48-h HBP change for prediction of 30-day mortality in adult patients with sepsis. This is a prospective observational study in an intensive care unit of a tertiary center. Patients aged 20 years or older who met SEPSIS-3 criteria were prospectively enrolled from August 2019 to January 2020. Plasma levels of HBP were measured at admission, 24 h, and 48 h and dynamic changes in HBP were calculated. The Primary endpoint was 30-day mortality. We tested whether the biomarkers could enhance the predictive accuracy of a multivariable predictive model. A total of 206 patients were included in the final analysis. 48-h HBP change (HBPc-48 h) had greater predictive accuracy of area under the curve (AUC: 0.82), followed by baseline HBP (0.79), PCT (0.72), lactate (0.71), and CRP (0.65), and HBPc-24 h (0.62). Incorporation of HBPc-48 h into a clinical prediction model significantly improved the AUC from 0.85 to 0.93. HBPc-48 h may assist clinicians with clinical outcome prediction in critically ill patients with sepsis and can improve the performance of a prediction model including age, SOFA score and Charlson comorbidity index.

A novel dual-phase PHSS consisting of lath martensite plus allotriomorphic δ ferrite (ALF) with nanoprecipitates was characterized by high-resolution field emission transmission electron microscopy for quenched, solid-solution-treated, and aged stainless steel. The effects of aging at various durations prior to H2O or liquid N2 quenching were investigated. Cu-rich nanoprecipitates evolve from body-centered cubic clusters to 9R Cu under quenching to 3R Cu and subsequently to face-centered cubic ε-Cu at various aging durations. Maximum hardness was observed after aging at 600 °C for 1 h. However, after this aging, both reversed austenite and Cu-rich nanoprecipitates coexisted in the martensite matrix. The segregation and diffusion of austenite-stabilizing elements promoted the nucleation of reversed austenite.

Background: Aspirin is the most commonly used antiplatelet agent for the prevention of cardiovascular diseases. However, a certain proportion of patients do not respond to aspirin therapy. The mechanisms of aspirin non-response remain unknown. The unique metabolomes in platelets of patients with coronary artery disease (CAD) with aspirin non-response may be one of the causes of aspirin resistance.Materials and Methods: We enrolled 29 patients with CAD who were aspirin non-responders, defined as a study subject who were taking aspirin with a platelet aggregation time less than 193 s by PFA-100, and 31 age- and sex-matched patients with CAD who were responders. All subjects had been taking 100 mg of aspirin per day for more than 1 month. Hydrophilic metabolites from the platelet samples were extracted and analyzed by nuclear magnetic resonance (NMR). Both 1D 1H and 2D J-resolved NMR spectra were obtained followed by spectral processing and multivariate statistical analysis, such as partial least squares discriminant analysis (PLS-DA).Results: Eleven metabolites were identified. The PLS-DA model could not distinguish aspirin non-responders from responders. Those with low serum glycine level had significantly shorter platelet aggregation time (mean, 175.0 s) compared with those with high serum glycine level (259.5 s). However, this association became non-significant after correction for multiple tests.Conclusions: The hydrophilic metabolic profile of platelets was not different between aspirin non-responders and responders. An association between lower glycine levels and higher platelet activity in patients younger than 65 years suggests an important role of glycine in the pathophysiology of aspirin non-response.

Lubricated sliding wear of amorphous (Zr55Cu30Ni10Al5)99.98Sc0.02/CuZr2 nanocrystal composite bulk metallic glasses (BMG) under various sliding velocities with a load of 20 N was investigated using the pin-on-disk test. After the wear test involving oil lubrication was performed, there was no wear induced new-phase transformation in the sample surface. Friction coefficients were within the range from 0.22 to approximately 0.29 under a 20-N load at different sliding velocities. Therefore, the calculated friction coefficients clearly indicated that the adhesion wear dominated from the experimental results. This deformation behavior resulted in a higher wear rate and wear coefficient. In addition, worn surfaces were characterized and examined under a scanning electron microscope (SEM) and optical microscope. The mechanism of high wear rate was clarified.

The offset between the center lines of the polished end-face and the fiber core has a significant effect on coupling efficiency. The initial contact point and the contact force are two of the most important parameters that induce the offset. This study proposes an image assistant method to find the initial contact point and a mathematical model to estimate the contact force when fabricating the double-variable-curvature end-face of single mode glass fiber. The repeatability of finding the initial contact point via the vision assistant program is 0.3 μm. Based on the assumption of a large deflection, a mathematical model is developed to study the relationship between the contact force and the displacement of the lapping film. In order to verify the feasibility of the mathematical model, experiments, as well as DEFORM simulations, are carried out. The results show that the contact forces are alomst linearly proportional to the feed amounts of the lapping film and the errors are less than 9%. By using the method developed in this study, the offset between the grinding end-face and the center line of the fiber core is within 0.15 to 0.35 μm.

This paper reveals the high-voltage insulation properties – namely the dielectric constant, dissipation factor, breakdown strength, and voltage – of epoxy resin samples of various thicknesses containing the microadditives albite, potassium feldspar, lithium glass, and zinc glass in different concentrations. 0.1 wt% KAlSi3O8 ceramic powders as fillers in 1 mm epoxy composites designed for insulation is taken as the choice for highest breakdown strength 36.6491 kV/mm. After that, 5 wt% Li-Bi-B-O glass at 35.4687 kV/mm, 10 wt% Zn-Bi-B-O glass at 35.0432 kV/mm, and 10 wt% NaAlSi3O8 at 33.6504 kV/mm. The increase of thickness more than 1 mm is not recommended in the practical application due to the decrease of breakdown strength. Multi-layer thin structure is recommended for insulation purpose.

Abstract Objective To investigate differences in the effectiveness of two lag screws, a regular bone plate, and locking bone plate fixation in treating horizontal oblique metacarpal shaft fractures. Materials and methods Horizontal oblique metacarpal shaft fractures were created in 21 artificial metacarpal bones and fixed using one of the three methods: (1) two lag screws, (2) a regular plate, and (3) a locking plate. All the specimens were subjected to the cantilever bending test performed using a material testing machine to enable recording of the force–displacement data of the specimens before failure. The Kruskal–Wallis test was used to compare failure force and stiffness values among the three fixation methods. Results The mean failure force of the two lag screw group (78.5 ± 6.6 N, mean + SD) was higher than those of the regular plate group (69.3 ± 17.6 N) and locking plate group (68.2 ± 14.2 N). However, the mean failure force did not significantly differ among the three groups. The mean stiffness value of the two lag screw group (17.8 ± 2.6 N/mm) was lower than those of the regular plate group (20.2 ± 10.5 N/mm) and locking plate group (21.8 ± 3.8 N/mm). However, the mean stiffness value did not significantly differ among the three groups. Conclusion The fixation strength of two lag screw fixation did not significantly differ from that of regular and locking bone plate fixation, as indicated by the measurement of the ability to sustain force and stiffness.