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The thermal stability of dislocation cellular structures in three additively manufactured (AM) austenitic stainless steels (SSs), 316L SS, 304L SS, and Al modified 316L SS (316L(Al)), were studied. Minor alloying elements, Mo and Al, were found affecting the stability of the cellular structures in AM austenitic SS, resulting in a stability ranking of AM 316L SS > AM 304L SS > AM 316L(Al) SS. As a result, their abilities towards recrystallization also differed. Owing to the high stacking fault energy (SFE) due to Al addition, AM 316L(Al) SS had the least stable subgrain cellular structure and exhibited the lowest recovery temperature. Although 316L SS possessed slightly higher SFE than 304L SS, the pinning effect due to Mo segregation at the cellular walls in AM 316L SS significantly enhanced its thermal stability. While the low-SFE AM 316L SS and AM 304L SS recovered their cellular structures via the equiaxed cell growth, the dislocation cellular walls in high-SFE AM 316L(Al) SS continuously vanished along a preferred direction. The fast recovery of cellular structures led to recrystallization retardation. The Hall–Petch model was found incapable of correlating cell size to strength because of the continuous weakening of cellular walls during heat treatment.

In this study, an experimental method is proposed to measure the real area of contact between an alumina sphere and an Al surface based on the adhesive transfer of the Au film and the scanning electron microscope in the back-scattered mode. A thin film of Au is sputtered on the alumina sphere before the indentation with the Al surface. After indentation, the interfaces of the alumina sphere and Al surface are observed by the scanning electron microscope. The contact area can be identified based on both the distributions of the alumina and Au on the alumina sphere and Al surface, respectively. The measured contact area at different nominal pressures are compared to predictions made by several popular theoretical elastic-plastic rough surface contact models.

Objective Potentially avoidable maternity complications (PAMCs) have been validated as an indicator of access to quality prenatal care. African-American mothers have exhibited a higher incidence of PAMCs, which has been attributed to unequal health coverage. The objective of this study was to assess if racial disparities in the incidence of PAMCs exist in a universally insured population. Study Design PAMCs in each racial group were compared relative to White mothers using multivariate logistic regression. Stratified subanalyses assessed for adjusted differences in the odds of PAMCs for each racial group within direct versus purchased care. Results A total of 675,553 deliveries were included. Among them, 428,320 (63%) mothers were White, 112,170 (17%) African-American, 37,151 (6%) Asian/Pacific Islanders, and 97,912 (15%) others. African-American women (adjusted odds ratio [aOR]: 1.05, 95% CI: 1.02–1.08) were more likely to have PAMCs compared with White women, and Asian women (aOR: 0.92, 95% CI: 0.89–0.95) were significantly less likely to have PAMCs compared with White women. On stratified analysis according to the system of care, equal odds of PAMCs among African-American women compared with White women were realized within direct care (aOR: 1.03, 95% CI: 1.00–1.07), whereas slightly higher odds among African-American persisted in purchased (aOR: 1.05, 95% CI: 1.01–1.10). Conclusion Higher occurrence of PAMCs among minority women sponsored by a universal health coverage was mitigated compared with White women. Protocol-based care as in the direct care system may help overcome health disparities.

The selenium isotopes lie at the heart of a tumultuous region of the nuclear chart where shape coexistence effects grapple with neutron-proton pairing correlations, triaxiality, and the impending proton drip line. In this work, a study of 72Se by internal conversion electron and γ-ray spectroscopy was undertaken with the SPICE and TIGRESS arrays. New measurements of the branching ratio and lifetime of the 02+ state were performed, yielding a determination of ρ2(E0;02+→01+)=29(3) milliunits. Two-state mixing calculations were performed that highlighted the importance of interpretation of such E0 strength values in the context of shape coexistence. peerReviewed

The energy calibration data collected for the \textsc{Majorana Demonstrator} is used to search for a Pauli Exclusion Principle (PEP) violating process in an atomic system where a new fermion is introduced through the electron-positron pair production. The signature of this PEP violating process would be found through the cascade of a pair-produced electron to a forbidden atomic level of Ge. An improved limit on the parameter (1/2)$��^{2}$, which quantifies the probability of a PEP violating process, is measured to be $