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Elucidating metal oxide growth mechanisms is essential for precisely designing and fabricating nanostructured oxides with broad applications in energy and electronics. However, current epitaxial oxide growth methods are based on macroscopic empirical knowledge, lacking fundamental guidance at the nanoscale. Using correlated in situ environmental transmission electron microscopy, statistically-validated quantitative analysis, and density functional theory calculations, we show epitaxial Cu2O nano-island growth on Cu is layer-by-layer along Cu2O(110) planes, regardless of substrate orientation, contradicting classical models that predict multi-layer growth parallel to substrate surfaces. Growth kinetics show cubic relationships with time, indicating individual oxide monolayers follow Frank-van der Merwe growth whereas oxide islands follow Stranski-Krastanov growth. Cu sources for island growth transition from step edges to bulk substrates during oxidation, contrasting with classical corrosion theories which assume subsurface sources predominate. Our results resolve alternative epitaxial island growth mechanisms, improving the understanding of oxidation dynamics critical for advanced manufacturing at the nanoscale. Understanding metal oxide growth mechanisms is essential for the precise design and fabrication of nanostructured oxides. Here, the authors use correlated in situ ETEM, data analysis, and DFT to show an unusual layer-by-layer adatom growth mechanism of 3D epitaxial Cu2O nano-islands, regardless of substrate orientation. [ABSTRACT FROM AUTHOR]

We provide an alternative proof that crosscaps are diffeomorphically stable. [ABSTRACT FROM AUTHOR]

Our objective was to examine the relationship between pregnancy desire among female adolescents and their perception of desire for pregnancy in their male partners. This is an observational cross-sectional study which examined 92 surveys administered to adolescent women between the ages of 14 to 19 years at two obstetrical care services serving a population from limited socioeconomic backgrounds. Participants were all pregnant or awaiting pregnancy test results. Participants were asked about their levels of pregnancy happiness and desire and their partners'' levels of pregnancy happiness and desire. Spearman''s correlation coefficient was calculated and discordant pairs were examined with McNemar''s test. Logistic regression was utilized to examine the relationship between male and female pregnancy happiness and desire. We found that there was a significant correlation between the adolescents'' feelings about pregnancy and their perceptions of their male partners'' feelings about pregnancy (0.326; P = .004). McNemar''s test indicated that male partners were significantly more likely to be reported to feel positively about the pregnancy than female partners (P = .017). Female adolescents who reported male partners who felt positively about the pregnancy were four times as likely to report having desired their pregnancy now or sooner (odds ratio [OR] = 4.35). We conclude that male partners may impact adolescent pregnancy desire. Further prospective studies are needed and male-focused adolescent pregnancy interventions should be developed. [Copyright &y& Elsevier]