The Impact Force of Large Boulders with Irregular Shape in Flash Flood and Debris Flow

Guang-Wu Si,Xiao-Qing Chen,Jian-Gang Chen,Jin-Bo Tang,Wan-Yu Zhao,Ke Jin 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.10

The impact force of large boulders carried by flash floods and debris flows is one of the main causes of structural damage. The elastoplastic modification model of the impact force was derived, and it was found that the impact force was significantly affected by large boulders with irregular shapes. However, a large boulder with an irregular shape is often simplified as an isovolumetric sphere or ellipsoid, which may lead to inaccurate calculation of the impact force. In this paper, a method to obtain the irregular shape of a large boulder in the field is proposed by combining field investigation, image processing, and graphic analysis. The irregular shape is described by a nonuniform rational B-spline (NURBS) curve. The curvature radii corresponding to the potential impact contact points on the surface of a large boulder, which can reflect the influence of the irregular shape, are extracted according to the concavity and convexity analysis. The results demonstrate that NURBS curves can describe irregular shapes both conveniently and accurately. The impact force was corrected by the elastic–plastic model, the impact force increased with increasing curvature radius, and the increase ratio of the impact force gradually decreased with increasing velocity. Compared with the isovolumetric sphere model and ellipsoid model, the impact force calculated by the ellipsoid model is closer to the results obtained in this paper. The reduction factor of the impact force is 0.03 − 0.16, which first increases significantly and then linearly increases with increasing curvature radius. In addition, the reduction factor of the impact force initially exhibits a significant decline with increasing velocity and then gradually stabilises. To simplify parameter selection, we suggest using the maximum curvature radius in the ellipsoid model as the calculation parameter in calculating the impact force of large boulders.

CpG methylated ribosomal RNA genes in relation to wing polymorphism in the rice pest Sogatella furcifera

Shi-Ke Liang,Zi-Qiang Liang,Xiao-Sui Zhou,Jia-Lin Chen,Guang-Hong Li,Fang-Hai Wang 한국응용곤충학회 2015 Journal of Asia-Pacific Entomology Vol.18 No.3

Sogatella furcifera is amajor rice pest that exhibits wing dimorphism. The methylation-sensitive representational difference analysis (MS-RDA) is widely used in plants and some animals to identify methylation differences in genomic DNA regions. However the method has been applied to insects very less. The objective of the current research was tomonitor differential cytosine methylations at CCGG sequences inmacropterous and brachypterous adults of female S. furcifera to determine the association between gene methylation and wing phenotypes using MS-RDA. After the second subtractive hybridization, two differentially methylated DNA fragments were obtained. These DNA fragments were then cloned into the pGEM-T vector and sequenced. One fragment fromthe positive hybridization was 464 bp, and highly similar to the 18S ribosomal RNA (rRNA) genes from some animals. Another fragment from the reverse hybridization was 453 bp, and homologous to the 28S rRNA gene of S. furcifera with a similarity rate as high as 99%. These results provide potential evidence that DNA methylation of rRNA genes may be related to wing phenotype variations in S. furcifera, and will facilitate future studies on the epigenetic mechanisms of insect wing polymorphism.

A Report of Chigger Mites on the Striped Field Mouse, Apodemus agrarius, in Southwest China

Yan-Ling Chen,Xian-Guo Guo,Tian-Guang Ren,Lei Zhang,Rong Fan,Cheng-Fu Zhao,Zhi-Wei Zhang,Ke-Yu Mao,Xiao-Bin Huang,Ti-Jun Qian 대한기생충학열대의학회 2021 The Korean Journal of Parasitology Vol.59 No.6

Different genomic DNA methylation patterns between male and female adults of white-backed planthoppers Sogatella furcifera

Mei Zhang,Jia-Lin Chen,Xiao-Sui Zhou,Shi-Ke Liang,Guang-Hong Li,Fang-Hai Wang 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.4

DNAmethylation plays a key role in gene regulation and phenotype variation in many organisms. The aimof thisstudy was to survey the frequency and variation of cytosine methylation at CCGG sequences in adult male andfemale planthoppers Sogatella furcifera, a major rice pest in Asia, and to determine the occurrence ofmethylationchanges associatedwith sexual dimorphismusingmethylation-sensitive amplification polymorphism. 1131DNAfragments including CCGG siteswere amplified using 36 pairs of selective primers: about 191methylated bandswere identified. Inmale planthoppers,we got a total of 581 bands, including 40 fully-methylated bands, 65 hemimethylatedbands and 476 none-methylated bands, so the fully-methylated ratio, hemi-methylated ratio andtotal methylated ratio were 6.88%, 11.19% and 18.07%, respectively. In the female planthopper, there were atotal of 550 bands, including 44 fully-methylated bands, 42 hemi-methylated bands and 464 none-methylatedbands. The fully-methylated ratio was 7.64% in female planthoppers, which was slightly higher than in themale planthoppers, however, the hemi-methylated ratio was lower (8.00%) in the female compared with themale planthopper. Altogether, 46 DNA bands displayed variable cytosine methylation patterns between maleand female samples: 20 of themoccurred only inmale samples and 26 only in female samples. Thus, the genomemethylation patterns are different between male and female adults. The results suggest that DNA methylationmight be related to sexual differentiation and development in S. furcifera.

MiRNA Synergistic Network Construction and Enrichment Analysis for Common Target Genes in Small-cell Lung Cancer

Zhang, Tie-Feng,Cheng, Ke-Wen,Shi, Wei-Yin,Zhang, Jin-Tao,Liu, Ke-Di,Xu, Shu-Guang,Chen, Ji-Quan Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Background: Small-cell lung cancer (also known as SCLC) is an aggressive form and untreated patients generally die within about 3 months. To obtain further insight into mechanism underlying malignancy with this cancer, an miRNA synergistic regulatory network was constructed and analyzed in the present study. Method: A miRNA microarray dataset was downloaded from the NCBI GEO database (GSE27435). A total of 546 miRNAs were identified to be expressed in SCLC cells. Then a miRNA synergistic network was constructed, and the included miRNAs mapped to the network. Topology analysis was also performed to analyze the properties of the synergistic network. Consequently, we could identified constitutive modules. Further, common target genes of each module were identified with CFinder. Finally, enrichment analysis was performed for target genes. Results: In this study, a miRNA synergistic network with 464 miRNAs and 2981 edges was constructed. According to the topology analysis, the topological properties between the networks constructed by LC related miRNAs and LC unrelated miRNAs were significantly different. Moreover, a module cilque0 could be identified in our network using CFinder. The module included three miRNAs (hsa-let-7c, hsa-let-7b and hsa-let-7d). In addition, several genes were found which were predicted to be common targets of cilque0. The enrichment analysis demonstrated that these target genes were enriched in MAPK signaling pathways. Conclusions: Although limitations exist in the current data, the results uncovered here are important for understanding the key roles of miRNAs in SCLC. However, further validation is required since our results were based on microarray data derived from a small sample size.

The Age-Related Orientational Changes of Human Semicircular Canals

Hui-Ying Lyu,Ke-Guang Chen,Dong-Ming Yin,Juan Hong,Lin Yang,Tian-yu Zhang,Peidong Dai 대한이비인후과학회 2016 Clinical and Experimental Otorhinolaryngology Vol.9 No.2

Objectives. Some changes are found in the labyrinth anatomy during postnatal development. Although the spatial orientation of semicircular canals was thought to be stable after birth, we investigated the age-related orientational changes of human semicircular canals during development. Methods. We retrospectively studied the computed tomography (CT) images of both ears of 76 subjects ranged from 1 to 70 years old. They were divided into 4 groups: group A (1–6 years), group B (7–12 years), group C (13–18 years), and group D (>18 years). The anatomical landmarks of the inner ear structures were determined from CT images. Their coordinates were imported into MATLAB software for calculating the semicircular canals orientation, angles between semicircular canal planes and the jugular bulb (JB) position. Differences between age groups were analyzed using multivariate statistics. Relationships between variables were analyzed using Pearson analysis. Results. The angle between the anterior semicircular canal plane and the coronal plane, and the angle between the horizontal semicircular canal plane and the coronal plane were smaller in group D than those in group A (P<0.05). The JB position, especially the anteroposterior position of right JB, correlated to the semicircular canals orientation (P<0.05). However, no statistically significant differences in the angles between ipsilateral canal planes among different age groups were found. Conclusion. The semicircular canals had tendencies to tilt anteriorly simultaneously as a whole with age. The JB position correlated to the spatial arrangement of semicircular canals, especially the right JB. Our calculation method helps detect developmental and pathological changes in vestibular anatomy.

Phylogenetic analysis and classification of insect achaete-scute complex genes

Nana Adwoa Nkuma Johnson,Yong Wang,Zhen Zeng,Guang-Dong Wang,Qin Yao,Ke Ping Chen 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2

Achaete-scute complex (ASC) genes play essential roles in neurogenesis of eukaryotes. Insect ASC genes are currently grouped into two distinct families, ASCa and ASCb. However, the identified insect ASCb family genes are not orthologous to known ASCb family genes from other animals such as nematode and mammal. Besides, many ASC genes have been annotated differently in GenBank. In this study, ASC genes from 41 insect species were obtained in silico and analyzed to clarify their evolutionary relationships with known ASC genes from other animals. Based on our analyses, a new naming system is suggested for classification of ASC genes. Firstly, a new family (ASCc) is added into the already existing two families and the gene of this family is named Asl (Achaetescute-like). Secondly, Ash4, Ash5 and Ash6 are used to name insect ASC genes that are not orthologous to ac, sc, l'sc and ase genes of Drosophila melanogaster and Ash1 to Ash3 genes of Bombyx mori. This naming system can be used to correct inappropriate annotations of insect ASC genes in GenBank and to classify newly identified insect ASC genes. Additionally, a vast difference was found in ASC gene composition among various insect species, suggesting that different insect species might have originated from various ancestral lineages.