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The recently discovered pressure-induced polymorphic transitions (PIPT) in high-entropy alloys (HEAs) have opened an avenue towards understanding the phase stability and achieving atomic structural tuning of HEAs. So far, whether there is any PIPT in the body-centered cubic (bcc) HEAs remains unclear. Here, we studied an ordered bcc-structured (B2 phase) AlCoCrFeNi HEA using in situ synchrotron radiation X-ray diffraction (XRD) up to 42 GPa and ex situ transmission electron microscopy, a PIPT to a likely-distorted phase was observed. These results highlight the effect of the lattice distortion on the stability of HEAs and extend the polymorphism into ordered bcc-structured HEAs.

Recently, an irreversible polymorphic transition from face-centered cubic to hexagonal close-packing was surprisingly observed under high pressure in the prototype CoCrFeMnNi high-entropy alloys (HEAs) by various research groups. This unexpected phase transition brings new insights into the stability of HEAs, and its irreversibility stimulates exploration for new HEAs via high-pressure compression synthesis. However, the onset pressure for the phase transition was reported to fluctuate over a vast range from ∼7 to above 49 GPa in the reported experiments. The reason for this inconsistency remains unclear and puzzles the HEA community. To address this problem, this work systematically investigates the effects of non-hydrostaticity and grain size. Our results demonstrate that larger deviatoric stress induced by the non-hydrostaticity of the pressure medium and larger grain size of the initial sample can both promote a phase transition and, therefore, considerably depress the onset pressure.

This study utilizes numerical simulations and dimensional analysis to investigate the impact of the two-phase outlet on flow field characteristics and separation efficiency of the separator. The study revealed a boundary layer separation at the water outlet, which was subsequently addressed to reduce energy losses in the separator. Dimensional analysis considered the influences of operational, structural, and physical parameters on the separator's performance. With other structural parameters held constant, separation efficiency is directly proportional to the ratio of inlet and oil-outlet diameter. Additionally, the separation efficiency is also associated with Re and the ratio of the inlet to the water-outlet diameter. When the diameter of the water outlet is constant, the axial vortex separator achieves optimal separation when the ratio of inlet and water-outlet diameter is 0.563, with a maximum separation efficiency of 97.00%. The optimal separation efficiency is reached at Re=22,908 under various operational conditions. Separation efficiency increases with water content, peaking at an inlet water content of 0.9 across different structural parameters. Separation efficiency shows an increase followed by a decrease with the rise in inlet flow rate(vi), achieving the best performance at vi=3m/s for the different separator structures studied. [ABSTRACT FROM AUTHOR]

In order to improve the performance of single-stage turbines, blade profiling optimization was conducted for the guide vane and rotor under design condition. Support vector regression (SVR) and non-dominated sorting genetic algorithm-II (NSGA-II) were used to execute the optimization, with the objective of maximizing the efficiency and total pressure ratio of single-stage turbines. The gas turbine chosen for the initial study was the KJ66, which is one of the most robust and primitive small gas turbine designs available. The influence mechanism of the stator and rotor profiling on flow field and performance was discussed. The results revealed that compared with the prototype, the adiabatic efficiency increased by 5.95% and the total pressure ratio increased by 0.9%. Furthermore, the matching of flows between the stator blade and rotor blade obviously improved. The optimized guide vane suppressed the flow separation by increasing the leading edge and improving the distribution of the inlet angle of attack. The load distribution of rotors with a 50% spanwise position changed from the original "C" loaded to post-loaded. The leading load obviously decreased, and the angle of attack was smaller than that of the prototype, which effectively weakened the flow separation at the leading edge of the rotor. Compared with the original rotor, the higher lean angle and pressure ratio of the turbine stage also improved. However, the leakage loss near the shroud of the rotor increased, which led to decreased efficiency. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the effects of miR-21 on the rats with proliferative diabetic retinopathy by regulating the transforming growth factor-beta (TGF-β) signaling pathway. MATERIALS AND METHODS: A total of 36 Sprague-Dawley rats were randomly divided into the normal group (n=12), model group (n=12), and inhibitor group (TGF-β signaling inhibitor) (n=12). No treatment was performed in the normal group, the diabetic retinopathy model was established in the model group, and the model was established in the inhibitor group after the intraperitoneal injection of the inhibitor. Then, the materials were sampled for detection. In each group, the retinal morphology was observed via hematoxylin-eosin (HE) staining, the expressions of TGF-β1 and Smad3 were detected via immunohistochemistry, the relative protein expression levels of phosphorylated Smad3 (p-Smad3) and TGF-β were determined via Western blotting, the expression of miR-21 was detected via quantitative Polymerase Chain Reaction (qPCR), and the hemodynamic indicators of the ocular tissues were detected using the color Doppler ultrasonography. RESULTS: The HE staining results revealed that the rats in the model group had evident retinal damage, which could be effectively improved using the inhibitor. According to the immunohistochemistry detection results, the positive expression level of TGF-β1 was substantially raised in both model group and inhibitor group compared with that in the normal group (p<0.05), and it was notably lower in the inhibitor group than that in the model group (p<0.05). Moreover, the three groups did not differ in the positive expression level of Smad3 (p>0.05). The Western blotting results showed that the model and inhibitor groups had remarkably higher relative protein expression levels of p-Smad3 and TGF-β1 than the normal group (p<0.05), and they were markedly lowered in the inhibitor group compared with those in the model group (p<0.05). According to the qPCR results, the expression level of miR-21 was notably elevated in both model group and inhibitor group compared with that in the normal group (p<0.05), and there was no difference in the expression level of miR- 21 between the former two groups (p>0.05). Finally, based on the color Doppler ultrasonography findings, the levels of the hemodynamic indicators substantially declined in both model group and inhibitor group compared with those in the normal group (p<0.05), and they were notably higher in the inhibitor group than those in the model group. CONCLUSIONS: We found that miR-21 regulates the TGF-β signaling pathway to affect the hemodynamics in the rats with proliferative diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Objective: To assess the common symptom clusters in cervical cancer patients treated with radiotherapy alone, chemoradiotherapy, or postoperative chemoradiotherapy, and evaluate differences among multi-modality treatment in these symptom clusters. Materials and Methods: Ninety-three patients diagnosed with cervical cancer were recruited to the survey, in which destination time was the fourth friday of radiotherapy. Symptoms of patients were evaluated by the Chinese version of the 13-item M.D. Anderson Symptom Inventory (MDASI). Results: Among the symptoms, lack of appetite was the most common and the most severe symptome, treatment modalities may have important effects on symptom clusters in cervical cancer patients undergoing radiotherapy. Conclusion: The results offer valuable information for the future development treatment-based symptom cluster intervention. [ABSTRACT FROM AUTHOR]

Objectives: Body roundness index (BRI) and body adiposity index (BAI) have been recently proposed to assess obesity. The objectives of this cross-sectional study were to compare their potential for identifying metabolic syndrome (MetS) with traditional obesity indices in Chinese postmenopausal women.Methods: A total of 817 participants were involved in this study. Odds ratio and corresponding 95% confidence intervals (CI) between MetS and all indices were evaluated by binary logistic regression analysis. Receiver operating characteristic curve and area under curve (AUC) were employed to evaluate the abilities to identify MetS among all the indices. The differences in the AUC values between traditional indices and BAI as well as BRI were also evaluated.Results: The upper values of all indices were significantly associated with the presence of MetS after adjusting for potential confounders, except for BAI. There were no significant differences in the AUC values between BRI and the traditional indices; however, the AUC values of all the traditional indices were significantly larger than that of BAI.Conclusions: Neither BAI nor BRI was superior to traditional obesity indices for predicting MetS. BAI showed the weakest predictive ability, while BRI showed potential for use as an alternative obesity measure in assessment of MetS. [ABSTRACT FROM AUTHOR]

Objective Serum uric acid levels have been reported to be associated with metabolic syndrome (MetS). However, few studies specifically examining the relationship between serum uric acid (SUA) levels and MetS in postmenopausal women have been reported in China. Thus, we conducted this study in order to assess the relationship between SUA levels and MetS in Chinese postmenopausal women. Methods A cross-sectional study of 1022 Chinese postmenopausal women (aged 42-80 years) who participated in annual health check-ups was employed. MetS was defined by National Cholesterol Education Program/Adult Treatment Panel III criteria (NCEP-ATP III). Of all the participants, 385 women were diagnosed with MetS (MetS group) and the others were without MetS (non-MetS group). SUA quartiles were defined as follows: Q1, < 3.9 mg/dl; Q2, 3.9-4.5 mg/dl; Q3, 4.6-5.1 mg/dl; Q4, 5.2-6.0 mg/dl. The association between SUA quartiles and MetS was assessed using binary logistic regression. Results The adjusted odds ratio (95% confidence interval) for the presence of metabolic syndrome in the highest SUA quartile vs. the lowest quartile was 3.768 (2.386-5.950) for all women ( p < 0.01) after adjusting for age, body mass index, blood urea nitrogen, serum creatinine, total cholesterol, low density lipoprotein cholesterol and C-reactive protein. The presence of MetS significantly increased in the second, third and fourth quartiles of SUA. The prevalence of MetS increased gradually with an increasing serum uric acid quartile ( p for trend < 0.001). Conclusion Higher SUA levels are positively and independently associated with the presence of MetS in Chinese postmenopausal women. [ABSTRACT FROM AUTHOR]