Stress analysis of rigid hanger of railway arch bridge based on vehicle-bridge coupling vibration

In order to study the stress of two new types of rigid hangers (circular steel and flat-plate rigid hangers) on the railway arch bridges, a finite element model of a railway through arch bridge was established. The influences of different types and sizes of hangers on the dynamic characteristics of the bridge were compared. Based on the established vehicle-bridge coupling vibration model, the influences of circular steel and flat-plate hanger sizes on the stress amplitude of hanger were discussed when the train passes through the bridge. The results show that when the flexible hanger of arch bridge was replaced by the rigid hanger, the symmetrical vertical bending frequency of bridge significantly increased. With the change of the size of flat-plate hanger, the torsional mode of the bridge was doped with the local vibration of the flat-plate hanger. With the increase of circular steel hanger diameter, the maximum stress amplitude of the hanger decreases as a whole. As for the flat-plate hanger, when the long side size b is the same, the maximum stress amplitude of the hanger decreases with the increase of the short side size d. When the short side size d is the same, with the increase of the long side size b, the maximum stress amplitude of the shorter hanger decreases, and the maximum stress amplitude of the longer hanger increases. When the size of the flat-plate hanger is too small or too large, the maximum stress amplitude is large

Simulating Spatiotemporal Dynamics of Sichuan Grassland Net Primary Productivity Using the CASA Model and In Situ Observations

Net primary productivity (NPP) is an important indicator for grassland resource management and sustainable development. In this paper, the NPP of Sichuan grasslands was estimated by the Carnegie-Ames-Stanford Approach (CASA) model. The results were validated with in situ data. The overall precision reached 70%; alpine meadow had the highest precision at greater than 75%, among the three types of grasslands validated. The spatial and temporal variations of Sichuan grasslands were analyzed. The absorbed photosynthetic active radiation (APAR), light use efficiency (ε), and NPP of Sichuan grasslands peaked in August, which was a vigorous growth period during 2011. High values of APAR existed in the southwest regions in altitudes from 2000 m to 4000 m. Light use efficiency (ε) varied in the different types of grasslands. The Sichuan grassland NPP was mainly distributed in the region of 3000–5000 m altitude. The NPP of alpine meadow accounted for 50% of the total NPP of Sichuan grasslands

The complete mitochondrial genome of Leiocassis crassilabris (Teleostei, Siluriformes: Bagridae)

The Leiocassis crassilabris is an important economic fish in China, and is widely distributed in south China, e.g. Yangtze River, Pearl River, and Min River, so it is a good model to study population genetics and geological changes of these regions. In this study, the complete mitochondrial genome sequence of L. crassilabris has been obtained with PCR. The gene arrangement and composition L. crassilabris of mitochondrial genome sequence are similar to most of the other vertebrates', which contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a non-coding control region with the total length of 16,530 bp. Except for eight tRNA and ND6 genes, other genes are encoded on heavy-strand (H-strand). Similar to most other vertebrates, the bias of G and C have universality in different region (genes). The complete mitochondrial genome sequence of L. crassilabris would contribute to better understand population genetics, conservation, biogeography, evolution of this lineage.The Leiocassis crassilabris is an important economic fish in China, and is widely distributed in south China, e.g. Yangtze River, Pearl River, and Min River, so it is a good model to study population genetics and geological changes of these regions. In this study, the complete mitochondrial genome sequence of L. crassilabris has been obtained with PCR. The gene arrangement and composition L. crassilabris of mitochondrial genome sequence are similar to most of the other vertebrates', which contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a non-coding control region with the total length of 16,530 bp. Except for eight tRNA and ND6 genes, other genes are encoded on heavy-strand (H-strand). Similar to most other vertebrates, the bias of G and C have universality in different region (genes). The complete mitochondrial genome sequence of L. crassilabris would contribute to better understand population genetics, conservation, biogeography, evolution of this lineage

Biogeographic history and high-elevation adaptations inferred from the mitochondrial genome of Glyptosternoid fishes (Sisoridae, Siluriformes) from the southeastern Tibetan Plateau

Background: The distribution of the Chinese Glyptosternoid catfish is limited to the rivers of the Tibetan Plateau and peripheral regions, especially the drainage areas of southeastern Tibet. Therefore, Glyptosternoid fishes are ideal for reconstructing the geological history of the southeastern Tibet drainage patterns and mitochondrial genetic adaptions to high elevations.</p

Mitochondrial genome of Acheilognathus barbatulus (Cypriniformes, Cyprinidae, Acheilognathinae): characterisation and phylogenetic analysis

Acheilognathus barbatulus is distributed in Yangtze River, Yellow River and Pearl River systems in China. Genome data can help to understand the phylogenetic relationships of A. barbatulus, but its complete mitochondrial genome has not been published. We determined the complete mitochondrial genome structure and characteristics of this species and constructed a comprehensive phylogenetic tree, based on mitochondrial genome data of several species of Acheilognathus, Rhodeus and Pseudorasbora parva. The complete length of the mitochondrial genome of A. barbatulus is 16726 bp. The genome is a covalently closed double-stranded circular molecule containing 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, a D-loop and a light strand replication initiation region. The base composition of the complete mitochondrial genome is A (29.33%) > T (27.6%) > C (26.12%) > G (16.95%), showing a strong AT preference and anti-G bias. All 13 PCGs have different degrees of codon preference, except for cytochrome c oxidase 1, which uses GTG as the start codon. All the PCGs use ATG as the start codon and the stop codon is dominated by TAG. The encoded amino acids Leu and Ser exist in two types, whereas the rest are all present as one type, except for tRNASer (GCT), which lacks the D-arm and has an incomplete secondary structure, all other tRNAs can be folded to form a typical cloverleaf secondary structure. Based on the 13 PCG tandems, the Maximum Likelihood and Bayesian trees were constructed, based on the concatenated sequence of 13 PCGs for the genera Acheilognathus and Rhodeus, with Pseudorasbora parva as the outgroup. Acheilognathus barbatulus, Acheilognathus tonkinensis and Acheilognathus cf. macropterus were clustered together and the most closely related. The results of this study enrich the mitochondrial genomic data of Acheilognathus and provide molecular and genetic base information for species conservation, molecular identification and species evolution of Acheilognathinae

Depth Map Regeneration via Improved Graph Cuts Using a Novel Omnidirectional Stereo Sensor

An integrated framework mainly focusing on stereo matching has been presented in this paper to obtain dense depth maps for a mobile robot that is equipped with a novel omnidirectional stereo vision sensor that is designed to obtain height information. The vision sensor is composed of a common perspective camera and two hyperbolic mirrors, which are separately fixed inside a glass cylinder. As the separation between the two mirrors provides much enlarged baseline, the precision of the system has improved correspondingly. Nevertheless, the large disparity space and image particularities that are different from general stereo vision system result in poor performance using common methods. To satisfy the reliability requirement by mobile robot navigation, we use improved graph cuts method, in which more appropriate three-variable smootheness model is proposed for general priors corresponding to more reasonable piecewise smoothness assumption since the well-known swap move algorithm can be applied to a wider class of functions. We also show the necessary modification to handle panoramic images, including deformed matching template, adaptable template scale. Experiment shows that this proposed vision system is feasible as a practical stereo sensor for accurate depth map generation. 1

Homatula guanheensis sp. nov. (Teleostei: Nemacheilidae), a new species of loach from Henan Province, China

Homatula are peculiar taxa in China, distributed in the Yellow River, Yangtze River, Pearl River, Lancang River drainage and Red River. At present, 17 valid species have been already reported in China.Homatula guanheensis sp. nov., a new species, is described from the Guanhe River of the HanJiang River drainage (a tributary of the Yangtze River), Xixia County, Henan province, China. The species can be distinguished from its congeners by a combination of molecular divergence in the Cytochrome oxidase I (CO I) and Cytochrome b (Cyt b) genes and morphological characters, including a shallower body with a uniform depth, differences in the widths of vertical brown bars on the body, body scale distribution, length of the dorsal adipose crest of the caudal peduncle, and the form of the intestine

Genome-wide identification and structural analysis of the BMP gene family in Triplophysa dalaica

Abstract Background Bone morphogenetic proteins (BMPs) are part of the transforming growth factor beta (TGF-β) superfamily and play crucial roles in bone development, as well as in the formation and maintenance of various organs. Triplophysa dalaica, a small loach fish that primarily inhabits relatively high elevations and cooler water bodies, was the focus of this study. Understanding the function of BMP genes during the morphogenesis of T. dalaica helps to clarify the mechanisms of its evolution and serves as a reference for the study of BMP genes in other bony fishes. The data for the T. dalaica transcriptome and genome used in this investigation were derived from the outcomes of our laboratory sequencing. Results This study identified a total of 26 BMP genes, all of which, except for BMP1, possess similar TGF-β structural domains. We conducted an analysis of these 26 BMP genes, examining their physicochemical properties, subcellular localization, phylogenetic relationships, covariance within and among species, chromosomal localization, gene structure, conserved motifs, conserved structural domains, and expression patterns. Our findings indicated that three BMP genes were associated with unstable proteins, while 11 BMP genes were located within the extracellular matrix. Furthermore, some BMP genes were duplicated, with the majority being enriched in the GO:0008083 pathway, which is related to growth factor activity. It was hypothesized that genes within the BMP1/3/11/15 subgroup (Group I) play a significant role in the growth and development of T. dalaica. By analyzing the expression patterns of proteins in nine tissues (gonad, kidney, gill, spleen, brain, liver, fin, heart, and muscle), we found that BMP genes play diverse regulatory roles during different stages of growth and development and exhibit characteristics of division of labor. Conclusions This study contributes to a deeper understanding of BMP gene family member expression patterns in high-altitude, high-salinity environments and provides valuable insights for future research on the BMP gene family in bony fishes

DNA Barcoding of Catfish: Species Authentication and Phylogenetic Assessment

As the global market for fisheries and aquaculture products expands, mislabeling of these products has become a growing concern in the food safety arena. Molecular species identification techniques hold the potential for rapid, accurate assessment of proper labeling. Here we developed and evaluated DNA barcodes for use in differentiating United States domestic and imported catfish species. First, we sequenced 651 base-pair barcodes from the cytochrome oxidase I (COI) gene from individuals of 9 species (and an Ictalurid hybrid) of domestic and imported catfish in accordance with standard DNA barcoding protocols. These included domestic Ictalurid catfish, and representative imported species from the families of Clariidae and Pangasiidae. Alignment of individual sequences from within a given species revealed highly consistent barcodes (98 % similarity on average). These alignments allowed the development and analyses of consensus barcode sequences for each species and comparison with limited sequences in public databases (GenBank and Barcode of Life Data Systems). Validation tests carried out in blinded studies and with commercially purchased catfish samples (both frozen and fresh) revealed the reliability of DNA barcoding for differentiating between these catfish species. The developed protocols and consensus barcodes are valuable resources as increasing market and governmental scrutiny is placed on catfish an