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Graphene oxide (GO) has been widely used to enhance the tensile/compressive strength of cement-based materials, whereas its shear reinforcing effect is still unknown. To verify the feasibility of GO as a shear reinforcement material, the shear reinforcing effect of GO on cement was experimentally investigated. The nanoscale Young’s modulus (E) of the GO-enhanced cement was measured with the peak force quantitative nanomechanical mapping method to clarify the enhancing mechanism. Results show that the addition of 0.02 and 0.04 wt% GO in cement could improve the shear strength by about 12 and 40%, respectively, which is mainly due to the enhanced cohesion, and at the nanoscale, the average E of the low-density hydration product increased by 1.6 and 13.2%, whereas that of high-density hydration product remains almost unchanged. There exist fewer nanoholes/cracks and unhydrated cement grains but more the high-density hydration product in GO-enhanced cement, implying a denser microstructure and higher hydration degree. GO can enhance the shear strength of cement because of its enhancing effects on the microstructure, nanoscale Young’s modulus of hydration products, as well as the hydration degree.

In‐memory computing and sensing can break through the limit of the traditional Von Neumann architecture where information storing and computing units are separated. Recently the topographic creation of a ferroelectric domain wall in separation of two antiparallel domains in LiNbO3 single‐crystal films integrated with the Si substrate has been the focus of such research. Here, the additional freedom of the light stimulus is reported to modulate the domain wall current significantly, enabling applications in nonvolatile domain wall memory, photodetector, and image recognition processor. These measurements shows the fantastic photosensitivity of 2D domain walls where the photocurrent varies nonlinearly against the accumulative pulse number. With this observation, an associated learning model is constructed to stimulate neuromorphic computing (with a recognition accuracy of 90%) using an artificial neuromorphic network of domain walls. The research promotes the multifold development of artificial intelligence using domain‐wall nanodevices sensitive to both optical and electrical stimulus. [ABSTRACT FROM AUTHOR]

Spermatogonial stem cells (SSCs) possess the characteristics of self-renewal and differentiation, as well as the ability to generate functional sperm. Their unique stemness has broad applications in male infertility treatment and species preservation. In rodents, research on SSCs has been widely reported, but progress is slow in large livestock such as cattle and pigs due to long growth cycles, difficult proliferation in vitro, and significant species differences. Previously, we showed that histone 3 (H3) lysine 9 (K9) trimethylation (H3K9me3) is associated with the proliferation of bovine SSCs. Here, we isolated and purified SSCs from calf testicular tissues and investigated the impact of different H3K9me3 levels on the in vitro proliferation of bovine SSCs. The enriched SSCs eventually formed classical stem cell clones in vitro in our feeder-free culture system. These clones expressed glial cell-derived neurotrophic factor family receptor alpha-1 (GFRα1, specific marker for SSCs), NANOG (pluripotency protein), C-KIT (germ cell marker), and strong alkaline phosphatase (AKP) positivity. qRT-PCR analysis further showed that these clones expressed the pluripotency genes NANOG and SOX2, and the SSC-specific marker gene GFRα1. To investigate the dynamic relationship between H3K9me3 levels and SSC proliferation, H3K9me3 levels in bovine SSCs were first downregulated using the methyltransferase inhibitor, chaetocin, or transfection with the siRNA of H3K9 methyltransferase suppressor of variegation 3-9 homologue 1 (SUV39H1). The EDU (5-Ethynyl-2′-deoxyuridine) assay revealed that SSC proliferation was inhibited. Conversely, when H3K9me3 levels in bovine SSCs were upregulated by transfecting lysine demethylase 4D (KDM4D) siRNA, the EDU assay showed a promotion of cell proliferation. In summary, this study established a feeder-free culture system to obtain bovine SSCs and explored its effects on the proliferation of bovine SSCs by regulating H3K9me3 levels, laying the foundation for elucidating the regulatory mechanism underlying histone methylation modification in the proliferation of bovine SSCs. [ABSTRACT FROM AUTHOR]

Simple Summary: Assisted reproductive technology including in vitro maturation (IVM) of oocytes, in vitro fertilization (IVF), and in vitro culture (IVC) of embryos is widely used both for humans and animals. In animal science and veterinary medicine, it is particularly important for livestock breeding. Although numerous efforts have been made, the development rates obtained with these techniques are still limited, especially in cattle. Vitamin C is a key nutrient that has multiple functions. To procure high-quality bovine oocytes, the effects of vitamin C on the IVM of bovine oocytes and embryo development at an early stage were investigated. We found that vitamin C supplementation at a tuned concentration improved bovine oocyte maturation and its combination in the media of IVM and IVC can potentially change the quality of bovine embryos. To obtain high-quality bovine oocytes, the effects of vitamin C (VC) on the IVM of bovine oocytes and early embryo development were investigated. The results showed the following. (1) The IVM medium containing 50 µg/mL VC improved the oocyte maturation rate but did not affect the parthenogenetic embryo development. (2) The IVC medium containing 20 µg/mL VC improved the cleavage rate of the IVF embryos and enhanced the mRNA transcriptions of pluripotency gene Oct4, Sox2, Cdx2, and Nanog in the blastocysts but had no effects on the blastocyst rate. (3) Combining supplementation of 50 µg/mL VC in IVM medium + 20 µg/mL VC in IVC medium (named as VC 50/20, similar hereinafter) elevated the cleavage rate of IVF embryos and enhanced the mRNA expressions of Oct4, Sox2, Cdx2, and Nanog in the blastocysts. (4) Combination of VC 0/20 and VC 50/20 enhanced the transcription of anti-apoptotic gene Bcl-2 and VC 50/0 weakened the transcription of pro-apoptotic gene Bax, while VC 0/40 and VC 0/60 increased Bax expression and diminished the Bcl-2/Bax ratio in blastocysts. Together, employing 50 µg/mL VC improves the IVM of bovine oocytes and combination of VC 50/20 potentially changes bovine embryo quality by enhancing the expressions of the pluripotency genes and regulating the expressions of apoptosis-related genes. [ABSTRACT FROM AUTHOR]

In order to study the reasonable support technology of weakly cemented soft rock roadway under water spraying condition, the 12307 return airway of Selian No.2 mine was taken as the background. The stress, deformation and plastic zone change characteristics of roadway surrounding under the condition of “anchor belt net and cable beam” support were studied by considering the strength and volume change of weakly cemented sandy mudstone with water spraying time, and the several improvement measures for support plan were proposed. The results of the study show that: under the condition of “anchor belt net and cable beam”, the surrounding rock radial displacement of weakly cemented soft rock roadway will continue to increase exponentially under the influence of water spraying. Finally, its moving distance from roof to floor and two sides will reach 750 mm and 200 mm respectively. After the improved support of “increasing the length of anchor bar, changing metal mesh to reinforced mesh sprayed concrete, and strengthening the support of roadway roof and two sides with anchor ropes”, the surrounding rock maximum radial displacement of weakly cemented soft rock roadway is only 29.0 mm, and the failure plastic zone depth is basically stable at 3.0 m, which well guarantees the safety of the roadway.