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Background: The COVID‐19 pandemic is an unprecedented health crisis that has affected in vitro fertilization practices globally. Previous studies have shown that SARS‐CoV‐2 impacts the quality of embryos by inducing an immunological response in infertile patients. In this study, the early embryonic development of SARS‐CoV‐2‐infected infertile patients was investigated. Methods: Sixty‐five SARS‐CoV‐2 infected infertile patients and 258 controls were involved in this study. The major outcome parameters for the cycle were analyzed, including the number of oocytes, maturation oocytes, available embryos per cycle, and embryo morpho kinetic characteristics. Results: From SARS‐CoV‐2 infection until oocyte retrieval, it took an average of 6.63 days. The results revealed that the number of oocytes and high‐quality embryos on day 3 dramatically reduced in SARS‐CoV‐2‐infected infertile patients. SARS‐CoV‐2 was detected in the follicular fluid of three infertile patients. SARS‐CoV‐2 infection had negatively impacted the number of oocytes in multivariate linear regression models. The early embryonic development in the SARS‐CoV‐2 infection group had a noticeable delay from the six‐cell stage to blastocyst stage. Conclusions: SARS‐CoV‐2 infection reduced the number of oocytes and high‐quality embryos on day 3. It delays the early embryonic development from the six‐cell stage to blastocyst stage and has a negative impact on the quality of embryos. [ABSTRACT FROM AUTHOR]

Ferroelectric memory is one of the most attractive emerging nonvolatile memory. Conventional methods to increase storage density in ferroelectrics include reducing the storage bit size or fabricating 3D stacks. However, the former will face a physical limit finally, and the integration of single‐crystalline ferroelectric oxide following the latter still remains a great challenge. Here, a new method is introduced to construct a scroll‐like 3D memory structure by self‐rolling‐up single‐crystalline ferroelectric oxides. PbZr0.3Ti0.7O3 single‐crystalline thin film is chosen as a prototype and epitaxially grown on another oxide stressor layer with a few lattice‐mismatch. Releasing such "Pb(Zr, Ti)O3/stressor" bilayered structure from the substrate induces self‐rolling‐up due to the internal stress from the lattice‐mismatch. High‐density information can be written in the form of switched ferroelectric domains on those flat "Pb(Zr, Ti)O3/stressor" membranes via piezoelectric force microscopy. In self‐rolling‐up membranes, information density can be experimentally enhanced up to 45 times. Theoretically, the freestanding "Pb(Zr, Ti)O3/stressor" membranes have a strongly driven force to self‐rolling‐up, and the area ratio can enhance 100–450 times, corresponding to an ultra‐high density information storage of 102 Tbit In−2. This study provides a new and general method to develop compact, high‐density, and 3D memories from oxide materials. [ABSTRACT FROM AUTHOR]

To improve the performances of AlGaN solar‐blind ultraviolet (UV) avalanche photodetectors (APDs), we propose a separate absorption and multiplication (SAM) AlGaN APD with a gradually doped charge layer. The calculation results indicate that the designed APD can significantly increase the maximum gain by almost 40%, and reduce the breakdown voltage by about 9% compared with the conventional AlGaN APD. The parameters of multiplication layer and p‐type layer are optimized, and the physical mechanism is described in detail, which provides theoretical guidance for high‐performance device structure design and experimental preparation. [ABSTRACT FROM AUTHOR]

The thymus plays an irreplaceable role as a primary lymphoid organ. However, the complicate processes of its development and involution are incompletely understood. Accumulating evidence indicates that non‐coding RNAs play key roles in the regulation of biological development. At present, the studies of the circRNA profiles and of circRNA‐associated competing endogenous RNAs (ceRNAs) in the thymus are still scarce. Here, deep‐RNA sequencing was used to study the biological mechanisms underlying the development process (from 2‐week‐old to 6‐week‐old) and the recession process (from 6‐week‐old to 3‐month‐old) of the mouse thymus. It was found that 196 circRNAs, 233 miRNAs and 3807 mRNAs were significantly dysregulated. The circRNA‐associated ceRNA networks were constructed in the mouse thymus, which were mainly involved in early embryonic development and the proliferation and division of T cells. Taken together, these results elucidated the regulatory roles of ceRNAs in the development and involution processes of the mouse thymus. [ABSTRACT FROM AUTHOR]