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Body-centered cubic (BCC) lightweight refractory high-entropy alloys (LWRHEAs) with Al contents have attracted much attention due to their low density and excellent mechanical properties. However, these typical lightweight alloys often suffer from poor room temperature plasticity. In this study, we prepared TiZrNbTa0.1Alx LWRHEAs by using a high-vacuum arc-melting technique and investigated the influence of Al content on the phase structures and mechanical properties. It was found that the TiZrNbTa0.1Al1 alloy showed a BCC solid solution matrix with some micrometer-sized Al3Zr5 precipitates and exhibited a density of 6.110 ± 0.003 g/cm3. The TiZrNbTa0.1Al1 alloy had a low mixed enthalpy of −20.831 kJ/mol, a compressive yield strength of 1037 ± 178 MPa, and a fracture plasticity of ∼6%. As a result of reducing the Al content, the TiZrNbTa0.1Al0.2 alloy showed a simple BCC phase structure without any precipitates and maintained a low density of 6.743 ± 0.008 g/cm3. The TiZrNbTa0.1Al0.2 alloy had a relatively high mixed enthalpy of −4.5577 kJ/mol, a high yield strength of 1022 ± 51 MPa, and a plasticity of >70%. The TEM analysis results demonstrated that the excellent mechanical properties of this LWRHEA were mainly attributed to the reducing Al content, which could elevate the mixed enthalpy of the alloy to eliminate the brittle Al3Zr5 phase and induce the formation of dense network dislocations at the grain boundaries. [ABSTRACT FROM AUTHOR]

System reliability directly affects the realization of software‐intensive system functions, which rely on both hardware and software. The operating status of hardware and software affect each other, and the continuous accumulation of their degraded performances will accelerate the occurrence of failures. However, the interaction relationship between hardware and software is often overlooked in most current research. In this paper, a new reliability analysis method is proposed for multi‐state software‐intensive systems with degradation accumulation effect and information transmission attenuation based on goal oriented (GO) methodology. First, a new function GO operator is created, and its operation formula is derived with the aid of Markov process theory. To quantify the impact of degradation accumulation on availability, non‐negative constant and random variable critical thresholds are set for the degradation state. Then, an effective optical power loss model is established to analyze the reliability of information transmission in the presence of attenuation. Next, the reliability analysis framework for multi‐state software‐intensive system is established based on the GO method. Finally, the proposed reliability analysis method is applied to the example of meter and decameter wavelength radio heliograph to demonstrate the applicability and feasibility of our work. The proposed model provides a more accurate reflection of the system reliability under actual operating conditions. [ABSTRACT FROM AUTHOR]

Objectives: Carcinosarcoma (CS) is a rare and biphasic malignancy characterised by a highly invasive biological nature and poor prognosis. This study explored the epidemiology, site-specific characteristics and survival outcome of CS., Design: We conducted a retrospective study in the Surveillance, Epidemiology and End Results (SEER) database (1975-2018) for primary CS., Setting and Participants: SEER database includes publicly available information from regional and state cancer registries in the US centres. A total of 5042 CS patients were identified. We selected the top five anatomic CS (uterus, double adnexa, lung, bladder and breast) patients for further analysis., Primary Outcome Measures: Incidence was estimated by geographical region, age, sex, race, stage and primary site. Trends were calculated using joinpoint regression. The cancer-specific survival (CSS) rate and initial treatment were summarised., Results: Nearly 80% of CS occurred in the uterus and double adnexa, followed by lung, bladder and breast. The elderly and black population presented the highest age-adjusted rate of CS. The rates of distant metastasis in CS progressively increased from 1989 to 2018. Atlanta was the area with the highest incidence at 0.7 per 100 000. Pulmonary and bladder CS more frequently occurred in men and were diagnosed with regional stage. Distant metastasis was mostly found in ovary/fallopian tube CS. Radiotherapy was more commonly applied in uterine CS, while adnexa CS cases were more likely to receive chemotherapy. Multiple treatments were more used in breast CS. Pulmonary CS seemed to suffer worse CSS (median: 9.92 months), for which radiotherapy might not provide survival benefits (HR 0.60, 95% CI 0.42 to 0.86). Compared with the common histological types in each site, CS had the shortest survival., Conclusions: CS has unique clinical features in each primary site. Substantial prognosis variances exist based on tumour locations. The aggressive course is the common feature in CS at all sites., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)