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Objective To investigate the effects of intraperitoneal injection of islet amyloid polypeptide (IAPP) on the expression profiles of circular RNAs (circRNAs) and messenger RNAs (mRNAs) in the brain tissue of Alzheimer's disease (AD) mice and wild-type (WT) mice. Methods Six 10-month-old male APP/PS1 transgenic AD model and C57 WT mice (20~30 g) were employed in this study. They were randomly divided into 2 groups, and further assigned into AD+IAPP (AD mice with IAPP intraperitoneal injection), WT+IAPP (WT mice with IAPP intraperitoneal injection), AD+PBS (AD mice injected with same dose of PBS intraperitoneally) and WT+PBS (WT mice with intraperitoneal injection of PBS) groups (n=3). After the intervention, total RNA was extracted from the brain tissue of 4 groups of mice, and gene chip sequencing was performed to screen differentially expressed circRNAs and mRNAs between AD+IAPP and WT+IAPP mice and between AD+PBS and WT+PBS mice. Among the differentially expressed circRNAs between AD+IAPP and WT+IAPP mice, 6 circRNAs were selected and subjected to real-time quantitative polymerase chain reaction (qRT-PCR) to verify the reliability of the microarray results. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomics (KEGG) pathway enrichment analysis were performed on the differentially expressed mRNAs. Subsequently, a competitive endogenous RNA (ceRNA) network was constructed for significantly differentially expressed circRNA_45921. Results There were 237 circRNAs significantly differentially expressed between AD+IAPP and WT+IAPP mice, of which 157 were up-regulated and 80 were down-regulated. Totally 663 significantly differentially expressed mRNAs were found, including 348 up-regulated and 315 down-regulated. The results of qRT-PCR showed that the differential expression of 6 circRNAs was consistent with the results of gene chip, indicating that the results of gene chip sequencing were reliable. GO enrichment analysis revealed that differentially up-regulated mRNAs were significantly enriched in nucleoside phosphate binding, organelles and metabolism processes of phosphate containing compounds. The differentially down-regulated mRNAs were significantly enriched in transmembrane signal receptor activity, supramolecular fibers and tissue development. KEGG enrichment analysis indicated that differentially upregulated mRNAs were mainly enriched in signal pathways such as insulin secretion, oxidative phosphorylation, and Parkinson's disease, while those down-regulated ones in signal pathways such as neuroactive ligand receptor interactions, calcium signaling pathways, tyrosine metabolism and phenylalanine metabolism. CeRNA network displayed that the circRNA_45921/miR-34c-5p/Eef2k regulatory network may play a role in the functioning of IAPP. Conclusion Intraperitoneal injection of IAPP alters the expression profiles of circRNA and mRNA in the brain tissues of AD mice and WT mice. Differentially expressed Paip2, Cdon, Ttr, and circRNA_45921/miR-34c-5p/Eef2k regulatory network may have regulatory roles in IAPP regulating the development of AD.

In this paper, according to the process of remote sensing monitoring of soil salinity and alkalinity process as well as the conditions, the remote sensing images were radiometrically corrected and aligned, and the remote sensing images were enhanced by using digital models to change the gray structure relationship of the image elements and change the gray value of the image elements, and then the changes in the patches of the remote sensing images were analyzed to extract the soil salinity and alkalinity data. In this paper, we also used statistical methods to analyze the acidity and salinity characteristics of soil samples, the soil spectral reflectance characteristics, and the sensitive bands for estimating the soil acidity and salinity characteristics, and we performed the multispectral inversion analysis of soil salinity on the basis of the spectral data. The results show that the remote sensing monitoring and early warning model of the soil salinization process established in this paper has a coefficient of determination R2 =0.697, RMSE=0.946, p=1.06*10-7 in the research calculations, and the root-mean-square error between predicted and measured values RMSE=2.33, which indicates that this model has a better performance in monitoring and prediction. The theoretical significance and practical value of this study are crucial for protecting the ecological environment and managing soil salinization.

The present situation of college students’ English learning is one of the key research topics. Some studies have found that different personality traits have a great impact on the English learning effect of college students. However, there is still a lack of detailed analysis and summary on the impact of a specific personality on the degree of English learning anxiety. Therefore, the questionnaire that the thesis uses is developed according to the Foreign Language Classroom Anxiety Scale (FLCAS), conducts random surveys for college students from different regions, majors and ages, and makes statistical analysis of the collected data using SPSS to explore the relationship between openness personality traits and the English-learning anxiety level of college students. After discussion and analysis, the results of this study can be divided into two aspects. Firstly, from the anxiety of the subjects, 60% of the 408 subjects have low anxiety about English learning, and their scores were very close to the medium anxiety level (99≤b≤132), while almost only a few respondents were at the high anxiety level. Secondly, there is a linear relationship between openness personality and English learning anxiety. According to the total score, the correlation was 0.338, showing a moderate correlation, and the significance level is 0.01. According to the research results, teachers can improve the teacher-student relationship and relieve students’ anxiety by innovating teaching methods and evaluation systems. However, the results may vary due to confounding factors such as major, gender and age.

The effects of curing temperature (20°C, 40°C and 60°C) and the addition of limestone powder (LP) (6% and 12%) on the capillary water absorption (CWA) of high-volume fly ash (HVFA) cement mortar were investigated. X-ray diffraction analysis and tests for chemically bound water content (CBWC), compressive strength and porosity were also conducted. It was found that, for a fly ash (FA) content exceeding 30%, the CWA increased significantly. When the FA content was 50%, the curing temperature was raised to 40°C or the LP content was 12%, the CBWC increased greatly. Increasing the curing temperature or adding LP increased the compressive strength and decreased the porosity of the HVFA cement mortar. Prediction of the water penetration depth in the HVFA cement mortar was consistent with the CWA results. The results of this work indicate that an increase in curing temperature or the addition of LP could be an efficient way of improving the CWA performance of HVFA cement mortar. [ABSTRACT FROM AUTHOR]

The spike protein (S) of SARS‐CoV‐2 is the major target of neutralizing antibodies and vaccines. Antibodies that target the receptor‐binding domain (RBD) of S have high potency in preventing viral infection. The ongoing evolution of SARS‐CoV‐2, especially mutations occurring in the RBD of new variants, has severely challenged the development of neutralizing antibodies and vaccines. Here, a murine monoclonal antibody (mAb) designated E77 is reported which engages the prototype RBD with high affinity and potently neutralizes SARS‐CoV‐2 pseudoviruses. However, the capability of E77 to bind RBDs vanishes upon encountering variants of concern (VOCs) which carry the N501Y mutation, such as Alpha, Beta, Gamma and Omicron, in contrast to its performance with the Delta variant. To explain the discrepancy, cryo‐electron microscopy was used to analyze the structure of an RBD–E77 Fab complex, which reveals that the binding site of E77 on RBD belongs to the RBD‐1 epitope, which largely overlaps with the binding site of human angiotensin‐converting enzyme 2 (hACE2). Both the heavy chain and the light chain of E77 interact extensively with RBD and contribute to the strong binding of RBD. E77 employs CDRL1 to engage Asn501 of RBD and the Asn‐to‐Tyr mutation could generate steric hindrance, abolishing the binding. In sum, the data provide the landscape for an in‐depth understanding of immune escape of VOCs and rational antibody engineering against emerging variants of SARS‐CoV‐2. [ABSTRACT FROM AUTHOR]

Byline: Jiong. Dai, Shanquan. Li, Xiaoxiong. Li, Wenhao. Xiong, Yongming. Qiu Background : Intraventricular hemorrhage (IVH) is an independent risk factor for both morbidity and mortality in patients with intracerebral [...]