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GH3536 and GH4169 nickel-based superalloys are widely used in aerospace engines and other hot-end components. In this paper，GH3536 and GH4169 alloy samples were fabricated by optimizing the process parameters using selective laser melting（SLM），the defect characteristics and microstructure of two alloys，as well as the effects of different homogenization temperatures and holding times on microstructure evolution，average grain size，and properties of two alloys were studied. The defect characteristics and microstructure were investigated by OM，SEM，and EDS, et al. The Vickers hardness meter was used to test the alloy’s microhardness. The results indicate that the as-built GH3536 alloy exhibits more defects，including pores，cracks，and lack of fusion， while only pores are present in as-built GH4169 alloy. The melt pool of alloy is eliminated by homogenization treatment，and the grains grow into equiaxed grains. M23C6 are found to distribute within grain boundaries and grain interiors of GH3536 alloy，while NbC are found to distribute within grain boundaries and grain interiors of GH4169 alloy，and the amount of precipitates is significantly reduced with the increase of homogenization temperature. The average grain size of GH3536 alloy is increased by 106.8% from 48.5 μm at 1130 ℃/1 h to 100.9 μm at 1250 ℃/4 h . The grain size of GH4169 alloy is increased by 53.3% from 57 μm at 1080 ℃/1 h to 87.4 μm at 1200 ℃/4 h.The homogenization treatment of GH3536 alloy and GH4169 alloy results in a significant decrease in microhardness of the former，from 262HV to 180-190HV，while the latter shows a significant increase，from 313HV to 430-450HV.

Purpose: The purpose of this study is to provide an alternative approach to teacher learning on top of the usual practices of listening to experts' lectures and conducting school-based activities among peers in China. A boundary-crossing lesson study (BCLS) through school-university partnership served as an example to illustrate how a class teacher's mindset changed towards her students in equal interactions with university scholars. Design/methodology/approach: With the lenses of action science theory and boundary-crossing learning theory, the study used qualitative research approach to collect and analyze data. One Chinese primary school class teacher from a workshop on narrative action research was selected as the case for this study. Interviewing, observation and document analysis were used to collect data. Data analysis methods included categorization and contextualization of the teacher's mindset change towards her student. Findings: The case teacher, Mrs. Li, collaborated closely in paired teaching with her university partner AP Yu in all the four phases of their BCLS. Each phase was marked with an interactive event such as dialogic illumination, reflexive theorization, embodied conversation, and fusion of teacher and trainer roles. With inspirational trust as a major interactive mechanism, Mrs. Li jumped out of her single-loop learning (changing strategies according to results) to double-loop learning (changing both strategies and values/values). As a result, her mindset changed from attribution to appreciation towards her low-achieving student. Originality/value: This study made contributions in two ways. First, it examined a class teacher's mindset change towards her student, rather than that of subject matter teachers towards their teaching materials and methods. Second, it revealed how reflective interactions in a special kind of BCLS by school teachers and university scholars may promote the teacher's mindset change. The findings further confirm that having differences as boundaries is not enough for teacher learning. For deep learning like Mrs. Li's mindset change, it requires a respectful and inspirational relationship between school teachers and university scholars in the BCLS.

Due to its lightweight, high strength, good machinability, and low cost, aluminum alloy has been widely used in fields such as aerospace, automotive, electronics, and construction. Traditional manufacturing processes for aluminum alloys often suffer from low material utilization, complex procedures, and long manufacturing cycles. Therefore, more and more scholars are turning their attention to the laser powder bed fusion (LPBF) process for aluminum alloys, which has the advantages of high material utilization, good formability for complex structures, and short manufacturing cycles. However, the widespread promotion and application of LPBF aluminum alloys still face challenges. The excellent printable ability, favorable mechanical performance, and low manufacturing cost are the main factors affecting the applicability of the LPBF process for aluminum alloys. This paper reviews the research status of traditional aluminum alloy processing and LPBF aluminum alloy and makes a comparison from various aspects such as microstructures, mechanical properties, application scenarios, and manufacturing costs. At present, the LPBF manufacturing cost for aluminum alloys is 2–120 times higher than that of traditional manufacturing methods, with the discrepancy depending on the complexity of the part. Therefore, it is necessary to promote the further development and application of aluminum alloy 3D printing technology from three aspects: the development of aluminum matrix composite materials reinforced with nanoceramic particles, the development of micro-alloyed aluminum alloy powders specially designed for LPBF, and the development of new technologies and equipment to reduce the manufacturing cost of LPBF aluminum alloy. [ABSTRACT FROM AUTHOR]

Objective Unravel the potential mechanism(s) of the on- and off-target actions of dopamine agonist therapy in both human prolactinoma tumors and neighboring stromal and immune cells. Design and Methods Five surgically resected prolactinomas (PRLomas) from 3 cabergoline (CBG)-treated patients and 2 treatment-naive patients were analyzed by using single-cell RNA sequencing (scRNA-seq) to compare the cellular composition and transcriptional landscape. Results Six major cell populations, namely tumor (88.2%), immune (5.6%), stromal (4.9%), progenitor cells (0.6%), proliferating cells (0.4%), and erythrocytes (0.2%), were observed. Tumor cells from CBG-treated patients expressed lower levels of genes that regulated hormone secretion, such as SCG2, VGF, TIMP1, NNAT, and CALD1, consistent with the inhibitory effects of CBG on hormone processing and secretion. Interestingly, we also observed an increased number of CD8+ T cells in the CBG-treated tissues. These cytotoxic CD8+ T cells expressed killing granule components such as perforin and the granzymes GZMB, GNLY, and KLRD1 as well as the inflammatory cytokine CCL5. Immune cell activation of these CD8+ T cells was further analyzed in a compartment-specific manner, and increased CD25 (IL2R) expression was noted in the CD8+ T cells from the CBG-treated samples. Additionally, and confirming prior reports, we noted a higher stromal cell population in the CBG-treated samples. Conclusions Our scRNA-seq studies revealed key differences in the transcriptomic features of CBG-treated and CBG-untreated PRLomas in both tumor and microenvironment cellular constituents, and for the first time, describe the previously unknown activation of CD8+ T cells following CBG treatment, which may play a role in the tumoricidal actions of CBG. [ABSTRACT FROM AUTHOR]