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Camouflage is a common technique in nature, enabling organisms to protect themselves from predators. The development of novel camouflage technologies, not only in fundamental science, but also in the fields of military and civilian applications, is of great significance. In this study, we propose a new type of deep-subwavelength four-layered meta-coating consisting of Si, Bi, Si, and Cr from top to bottom with total thickness of only ∼355 nm for visible-infrared compatible camouflage. The visible color and the infrared emission properties of the meta-coating can be independently adjusted. Colorful meta-coating for visible camouflage can be obtained by changing the thickness of top Si layer, while the selective high emissivity in non-atmospheric window for infrared camouflage remains. Due to the deep-subwavelength properties, the meta-coating shows high angle tolerance in both visible and infrared regions. The compatible camouflage capability of our proposed meta-coating in the visible-infrared region is validated under different environments. The deep-subwavelength, angular insensitivity, visible-infrared compatibility and large-area fabrication feasibility promise the meta-coating an effective solution for camouflage in various applications such as military weapons and anti-counterfeiting.

Two-characters continuation, which is a string with two characters emerging in linear sequence, can break through the encapsulation and independence of long solidified language chunks (words and phrases). In this way, two-characters continuation can measure the information of not only static language units (words and phrases) but also their combination in the text. Therefore, two-characters continuation is used as a measurement unit for investigating Chinese text's difficulty, to enhance the accuracy of measuring text's difficulty. Three different measurement methods of text's difficulty are proposed, which are respectively based on "continuation index of character", "new and stable two-characters continuation" and "emerging tendency of two-characters continuation". The results show that compared to other two methods, the measurement method of text's difficulty based on new and stable two-characters continuations has better effectiveness, whose accuracies for measuring text's difficulty with 6 levels, 3 levels and 2 levels difficulties can reach 36.4%, 64.6% and 79.6%, respectively. In addition, compared to Jiang and Wu's research works, the above measurement method also shows a better effectiveness. [ABSTRACT FROM AUTHOR]

p-type semiconductors are significant for integrated nanoelectronics. Tellurium (Te), a mono-elemental material, is a p-type semiconductor with high mobility. Its outstanding performance renders it widely applicable in the fields of electronics and optoelectronics. However, the wafer-scale fabrication of Te thin films is challenging. In this study, we reported an ion-bean sputtered Te thin film and investigated the effects of annealing temperatures. Annealing-induced crystallization kinetics were assessed through Raman spectroscopy, x-ray diffraction, and atomic force microscopy. After annealing, the film's conductivity increased from 10−5 to 10−4 S and mobility from 18 to 53 cm2 V−1 s−1. Dual AC resonance tracking switching spectroscopy piezoelectric force microscopy is used to investigate piezo/ferroelectric properties. The coercive voltages are −2 and 4 V respectively, and the effective piezoelectric coefficient (d33) is 40 pm/V. Butterfly and phase-switching loops demonstrate its possible ferroelectricity. The Te thin film has potential applications in optoelectronics, nonvolatile memory devices, and neuromorphic computation. [ABSTRACT FROM AUTHOR]

Assisted reproduction technology (ART) procedures are often impacted by post-ovulatory aging (POA), which can lead to reduced fertilization rates and impaired embryo development. This study used RNA sequencing analysis and experimental validation to study the similarities and differences between in vivo- and vitro-matured porcine oocytes before and after POA. Differentially expressed genes (DEGs) between fresh in vivo-matured oocyte (F_vivo) and aged in vivo-matured oocyte (A_vivo) and DEGs between fresh in vitro-matured oocyte (F_vitro) and aged in vitro-matured oocyte (A_vitro) were intersected to explore the co-effects of POA. It was found that "organelles", especially "mitochondria", were significantly enriched Gene Ontology (GO) terms. The expression of genes related to the "electron transport chain" and "cell redox homeostasis" pathways related to mitochondrial function significantly showed low expression patterns in both A_vivo and A_vitro groups. Weighted correlation network analysis was carried out to explore gene expression modules specific to A_vivo. Trait–module association analysis showed that the red modules were most associated with in vivo aging. There are 959 genes in the red module, mainly enriched in "RNA binding", "mRNA metabolic process", etc., as well as in GO terms, and "spliceosome" and "nucleotide excision repair" pathways. DNAJC7, IK, and DDX18 were at the hub of the gene regulatory network. Subsequently, the functions of DDX18 and DNAJC7 were verified by knocking down their expression at the germinal vesicle (GV) and Metaphase II (MII) stages, respectively. Knockdown at the GV stage caused cell cycle disorders and increase the rate of abnormal spindle. Knockdown at the MII stage resulted in the inefficiency of the antioxidant melatonin, increasing the level of intracellular oxidative stress, and in mitochondrial dysfunction. In summary, POA affects the organelle function of oocytes. A_vivo oocytes have some unique gene expression patterns. These genes may be potential anti-aging targets. This study provides a better understanding of the detailed mechanism of POA and potential strategies for improving the success rates of assisted reproductive technologies in pigs and other mammalian species. [ABSTRACT FROM AUTHOR]

Y‐box binding protein 1 (YBX1) is a member of the family of DNA‐ and RNA‐binding proteins that play crucial roles in multiple aspects, including RNA stabilization, translational repression, and transcriptional regulation; however, its roles in embryo development remain less known. In this study, to investigate the function of YBX1 and its mechanism of action in porcine embryo development, YBX1 was knocked down by microinjecting YBX1 siRNA at the one‐cell stage. YBX1 is located in the cytoplasm during embryonic development. The mRNA level of YBX1 was increased from the four‐cell stage to the blastocyst stage but was significantly decreased in YBX1 knockdown embryos compared with the control. Moreover, the percentage of blastocysts was decreased following YBX1 knockdown compared with the control. Defecting YBX1 expression increased maternal gene mRNA expression and decreased zygotic genome activation (ZGA) gene mRNA expression and histone modification owing to decreased levels of N6‐methyladenosine (m6A) writer N6‐adenosine‐methyltransferase 70 kDa subunit (METTL3) and reader insulin‐like growth factor 2 mRNA‐binding protein (IGF2BP1). In addition, IGF2BP1 knockdown showed that YBX1 regulated the ZGA process through m6A modification. In conclusion, YBX1 is essential for early embryo development because it regulates the ZGA process. [ABSTRACT FROM AUTHOR]

A new measurement method of Chinese texts' difficulty based on the digital analysis of two-character continuations is proposed, which is ' i  + 1' measurement model of language difficulty. The new method shifts the focus of the measurement of text difficulty from language units and grammatical complexity to combinations of language units, which breaks the limitations of existent methods of the measurement of Chinese texts' difficulty. First, the effectiveness of the two-character continuations in the differentiation of texts difficulties is verified. Second, for the application of the ' i  + 1' model in measuring text difficulty, the pedagogy and language acquisition theories are analyzed to check its rationality. Third, a corpus of two-character continuations is built up, with which the empirical values of '1' for two-character continuations with various difficulty levels in the ' i  + 1' measurement model are obtained. Subsequently, the testing texts, the two-character continuations corpus, and the empirical values of '1' are integrated to test the validity of the ' i  + 1' model in the measurement of text difficulty. The research shows that, compared to those methods based on the complex features of language, the ' i  + 1' measurement model based on two-character continuations, with fewer indicators and more convenience in the measurement, demonstrates better measurement result of text difficulty. [ABSTRACT FROM AUTHOR]

Background: Activating transcription factor 7 (ATF7) is a member of the ATF/cAMP response element (CRE) B superfamily. ATF2, ATF7, and CRE‐BPa are present in vertebrates. Drosophila and fission yeast have only one homologue: dATF2 and Atf1, respectively. Under normal conditions, ATF7 promotes heterochromatin formation by recruiting histone H3K9 di‐ and tri‐methyltransferases. Once the situation changes, all members are phosphorylated by the stress‐activated kinase P38 in response to various stressors. However, the role of ATF7 in early porcine embryonic development remains unclear. Results: In this study, we found that ATF7 gradually accumulated in the nucleus and then localized on the pericentric heterochromatin after the late 4‐cell stage, while being co‐localized with heterochromatin protein 1 (HP1). Knockdown of ATF7 resulted in decreases in the blastocyst rate and blastocyst cell number. ATF7 depletion resulted in downregulation of HP1 and histone 3 lysine 9 dimethylation (H3K9me2) expression. These effects were alleviated when P38 activity was inhibited. High temperatures increased the expression level of pP38, while reducing the quality of porcine embryos, and led to ATF7 phosphorylation. The expression level of H3K9me2 and HP1 was decreased and regulated by P38 activity. Conclusion: Stress‐induced ATF7‐dependent epigenetic changes play important roles in early porcine embryonic development. [ABSTRACT FROM AUTHOR]