Topological Crystalline Insulators with C2C_2 Rotation Anomaly

Based on first-principles calculations and symmetry-based indicator analysis, we find a class of topological crystalline insulators (TCIs) with $C_2$ rotation anomaly in a family of Zintl compounds, including $\mathrm{Ba}_{3}\mathrm{Cd}_{2}\mathrm{As}_{4}$, $\mathrm{Ba}_{3}\mathrm{Zn}_{2}\mathrm{As}_{4}$ and $\mathrm{Ba}_{3}\mathrm{Cd}_{2}\mathrm{Sb}_{4}$. The nontrivial band topology protected by coexistence of $C_2$ rotation symmetry and time-reversal symmetry $T$ leads to two surface Dirac cones at generic momenta on both top and bottom surfaces perpendicular to the rotation axis. In addition, ($d-2$)-dimensional helical hinge states are also protected along the hinge formed by two side surfaces parallel with the rotation axis. We develop a method based on Wilson loop technique to prove the existence of these surface Dirac cones due to $C_2$ anomaly and precisely locate them as demonstrated in studying these TCIs. The helical hinge states are also calculated. Finally, we show that external strain can be used to tune topological phase transitions among TCIs, strong Z$_2$ topological insulators and trivial insulators.Comment: 10 pages, 10 figure

Clustering and Differentiation of glr-3 Gene Function and Its Homologous Proteins

In order to adapt to the low temperature environment, organisms transmitexcitement to the central system through the thermal sensing system, whichis a classic reflex reaction. The cold receptor GLR-3 perceives cold and produces cold avoidance behavior through peripheral sensory neurons ASER.In order to further understand the gene encoding of the cold sensing glr-3gene and the evolution of its homologous gene group function and proteinfunction, the nucleotide sequence and amino acid sequence of the glr-3gene and its homologous gene in 24 species were obtained and compared.By clustering with the GRIK2 gene sequence of Rana chensinensis, the bioinformatics method was used to predict and sequence analyze the change ofgene, evolution rate, physical and chemical properties of protein, glycosylation sites, phosphorylation sites, secondary structure and tertiary structureof protein. The analysis results show that the glr-3 gene and its homologousgene have obvious positive selection effect. The protein prediction analysisshowed that the glr-3 gene and its homologous genes encoded proteinsin these 25 species were hydrophilic proteins, and the proportion of sidechains of aliphatic amino acids was high. The transmembrane helix waswidespread and there were more N-glycosylation sites and O-glycosylationsites. The protein phosphorylation sites encoded were serine, threonine andtyrosine phosphorylation sites. Secondary structure prediction showed thatthe secondary structure units of the encoded protein were α-helix, β-turn,random coil and extended chain, and the proportion of α-helix was the largest. This study provides useful information on the evolution and function ofthe cold sensing gene glr-3 and its homologous genes

Crystal and Electronic Structure of GaTa4_4Se8_8 From First-Principle Calculations

GaTa$_4$Se$_8$ belongs to the lacunar spinel family. Its crystal structures is still a puzzle though there have been intensive studies on its novel properties, such as the Mott insulator phase and superconductivity under pressure. In this work, we investigate its phonon spectra through first-principle calculations and proposed it most probably has crystal structure phase transition, which is consistent with several experimental observations. For the prototype lacunar spinel with cubic symmetry of space group $F\bar{4}3m$, its phonon spectra have three soft modes in the whole Brillouin zone, indicating the strong dynamical instability of such crystal structure. In order to find the dynamically stable crystal structure, further calculations indicate two new structures of GaTa$_4$Se$_8$, corresponding to $R3m$ and $P\bar{4}2_{1}m$, verifying that at the ambient pressure, there does exist structure phase transition of GaTa$_4$Se$_8$ from $F\bar{4}3m$ to other structures when the temperature is lowered. We also performed electronic structure calculation for $R3m$ and $P\bar{4}2_{1}m$ structure, showing that $P\bar{4}2_{1}m$ structure GaTa$_4$Se$_8$ is band insulator, and obtained Mott insulator state for $R3m$ structure by DMFT calculation under single-band Hubbard model picture when interaction parameter U is larger than 0.40 eV vs. band width of 0.25 eV. It is reasonable to assume that while lowering the temperature, $F\bar{4}3m$ structure GaTa$_4$Se$_8$ becomes $R3m$ structure GaTa$_4$Se$_8$ first, then $P\bar{4}2_{1}m$ structure GaTa$_4$Se$_8$, because of the symmetry of $P\bar{4}2_{1}m$ is lower than $R3m$ after Jahn-Teller distortion. The structure transition may explain the magnetic susceptibility anomalous at low temperature

A Method of Multi-component Signal Detection Based on Differential Nonlinear Mode Decomposition

In order to detect the multi-component signal from the noise and chaos, a method based on the differential nonlinear mode decomposition (DNMD) is proposed in this paper. This new analysis approach applies the differential to the original signal. Then the nonlinear mode decomposition (NMD) is used to obtain a series of meaningful nonlinear modes, which has the advantage of extracting high frequency components with small amplitudes and learns from the superiority of NMD such as noise robust. Finally, the spectrum analysis is used to the decomposed components. The analysis of simulation signals and the real underwater signal is given to demonstrate the effectiveness of this method. Proposed method can detect multi-component signals of time-varying amplitude without fake frequency under the condition of noise and chaos. Compared with traditional decomposition methods, the peaks of Hilbert marginal spectrum of proposed method are sharper, and R2, R3 are higher

A Method of Multi-component Signal Detection Based on Differential Nonlinear Mode Decomposition

In order to detect the multi-component signal from the noise and chaos, a method based on the differential nonlinear mode decomposition (DNMD) is proposed in this paper. This new analysis approach applies the differential to the original signal. Then the nonlinear mode decomposition (NMD) is used to obtain a series of meaningful nonlinear modes, which has the advantage of extracting high frequency components with small amplitudes and learns from the superiority of NMD such as noise robust. Finally, the spectrum analysis is used to the decomposed components. The analysis of simulation signals and the real underwater signal is given to demonstrate the effectiveness of this method. Proposed method can detect multi-component signals of time-varying amplitude without fake frequency under the condition of noise and chaos. Compared with traditional decomposition methods, the peaks of Hilbert marginal spectrum of proposed method are sharper, and R2, R3 are higher

Identification of candidate genes for soybean seed coat-related traits using QTL mapping and GWAS

Seed coat color is a typical morphological trait that can be used to reveal the evolution of soybean. The study of seed coat color-related traits in soybeans is of great significance for both evolutionary theory and breeding practices. In this study, 180 F10 recombinant inbred lines (RILs) derived from the cross between the yellow-seed coat cultivar Jidou12 (ZDD23040, JD12) and the wild black-seed coat accession Y9 (ZYD02739) were used as materials. Three methods, single-marker analysis (SMA), interval mapping (IM), and inclusive composite interval mapping (ICIM), were used to identify quantitative trait loci (QTLs) controlling seed coat color and seed hilum color. Simultaneously, two genome-wide association study (GWAS) models, the generalized linear model (GLM) and mixed linear model (MLM), were used to jointly identify seed coat color and seed hilum color QTLs in 250 natural populations. By integrating the results from QTL mapping and GWAS analysis, we identified two stable QTLs (qSCC02 and qSCC08) associated with seed coat color and one stable QTL (qSHC08) related to seed hilum color. By combining the results of linkage analysis and association analysis, two stable QTLs (qSCC02, qSCC08) for seed coat color and one stable QTL (qSHC08) for seed hilum color were identified. Upon further investigation using Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, we validated the previous findings that two candidate genes (CHS3C and CHS4A) reside within the qSCC08 region and identified a new QTL, qSCC02. There were a total of 28 candidate genes in the interval, among which Glyma.02G024600, Glyma.02G024700, and Glyma.02G024800 were mapped to the glutathione metabolic pathway, which is related to the transport or accumulation of anthocyanin. We considered the three genes as potential candidate genes for soybean seed coat-related traits. The QTLs and candidate genes detected in this study provide a foundation for further understanding the genetic mechanisms underlying soybean seed coat color and seed hilum color and are of significant value in marker-assisted breeding

Regulation of non-classical immune parameters in immune thrombocytopenic purpura mice by a spleen-invigorating, qi-replenishing and blood-containing formula

AbstractObjectiveThis study investigated the regulatory effect of non-classical immune parameters on immune thrombocytopenic purpura (ITP) mice by a spleen-invigorating, qi-replenishing and blood-containing formula (SQBF).MethodA total of 80 BALB/c mice were randomly divided into four equal groups (20 mice each): control group, model group, prednisone group and spleen-invigorating, qi-replenishing and blood-containing (SQBF) group. Mice in the model group, prednisone group, and SQBF group were administered anti-platelet serum to induce ITP. The dynamic variations of platelet counts in ITP mice were measured with an automatic blood analyzer before modeling and 48 h, and 8, 12 and 15 days following APS injection. Levels of β-endorphin (β-EP), vasoactive intestinal peptide (VIP) and salivary IgA (SIgA) were detected by enzyme-linked immunosorbent assay (ELISA) on 15th day of experiment.ResultsSQBF enhanced peripheral blood platelet counts in ITP mice similar to that of prednisone, and both groups showed a statistically significant response compared with the model group (P < .01). The SQBF significantly decreased β-EP levels compared with the model and prednisone intervention groups (P < .05), significantly increased the levels of VIP and SIgA in ITP mice compared with the model group (P < .05) and had significant protective effects on the thymus of ITP mice compared with the model group (P < .01).ConclusionsThe SQBF had a similar effect to prednisone with regards to enhancing peripheral blood platelet counts in ITP mice. Furthermore, it decreased β-EP levels and increased VIP and SIgA, and protected the thymus. This shows that, on base of the brain-gut axis functions, some non-classical immune vascular active factors or neurotransmitters are also involved in immune responses, and also have relationship with the onset of ITP and bleeding and/or hemostasis. It needs further study to determine whether a change in these active factors is related to immediate hemostasis

Changes in Public Perception and Behaviors under Compound Heatwave in COVID-19 Epidemic — Beijing, China, 2020

What is already known about this topic? Dramatic heatwaves frequently occurred simultaneously with the coronavirus disease 2019 (COVID-19) pandemic worldwide in 2020 and posed public health challenges. Public risk perceptions and behavioral responses to this compound risk need to be addressed. What is added by this report? During heatwaves, the proportion of individuals who perceived COVID-19 to be more concerning than heatwaves decreased by 9.4%, and the behavior of continuously wearing masks reduced by 20.6%. Heatwave exposures also corresponded to an average decline of 58% in the likelihood of continuously wearing masks and a decline of 41% in taking well-ventilated public transportation. What are the implications for public health practice? At-risk populations should be effectively prepared to respond to compounded risks from heatwaves occurring at the same time as COVID-19 outbreaks to better address threats caused by climate change

Advances in application of single-cell RNA sequencing in cardiovascular research

Single-cell RNA sequencing (scRNA-seq) provides high-resolution information on transcriptomic changes at the single-cell level, which is of great significance for distinguishing cell subtypes, identifying stem cell differentiation processes, and identifying targets for disease treatment. In recent years, emerging single-cell RNA sequencing technologies have been used to make breakthroughs regarding decoding developmental trajectories, phenotypic transitions, and cellular interactions in the cardiovascular system, providing new insights into cardiovascular disease. This paper reviews the technical processes of single-cell RNA sequencing and the latest progress based on single-cell RNA sequencing in the field of cardiovascular system research, compares single-cell RNA sequencing with other single-cell technologies, and summarizes the extended applications and advantages and disadvantages of single-cell RNA sequencing. Finally, the prospects for applying single-cell RNA sequencing in the field of cardiovascular research are discussed