183 research outputs found
Interfacial Bond Properties between Normal Strength Concrete and Epoxy Resin Concrete
No full textFunding Information: This study was sponsored by the Natural Science Basic Research Program of Shaanxi (Grant no. 2020JQ-377). The financial support is gratefully appreciated. The assistance for experimental studies from China Chengdu Datong Road Bridge Machinery Company Limited, Chang'an University, is also appreciated. The China Scholarship Council is acknowledged for the financial support and assistance to the first author. Publisher Copyright: © 2021 Nannan Sun et al.It is necessary to pay attention to the bonding strength of the interface between precast normal strength concrete (NSC) and cast-in-place epoxy resin concrete (EMR) when using EMR as a repair or filling material or an overlay in bridges' rehabilitation. However, the performances of epoxy concrete are different due to differential mix ratios; thus, the bonding properties between various epoxy resin concrete and cement concrete are not completely the same. This article investigated the interfacial bond properties between NSC and ERC by direct tensile, push-out, and slant shear test with specimens of special size and structure and observed the interfacial bond strength and corresponding failure modes. The minimum bond strength under direct tension was 0.72 MPa, while the minimum bond strength was 1.71 MPa and 3.19 MPa for the push-out test and slant shear test, respectively. Results indicated that the slant shear test specimens with an inclination angle of 45° are not suitable for the slant shear test due to higher compressive stress. Furthermore, the cohesion and friction coefficient of interface bond strength were calculated inversely in accordance with the results obtained from the corresponding direct tensile and slant shear tests. The minimum cohesion value was 1.71 MPa, and the minimum friction coefficient value was 0.46.Peer reviewe
Data for: Application of Terahertz Time Domain Spectroscopy for NDT of Oxide-Oxide Ceramic Matrix Composites
No full textIn this paper the measurement results show the feasibility of the pulsed terahertz technique for NDT of oxide-oxide CMC materials. Hidden defects, delamination or moist areas can be detected quantitatively. Furthermore, the boundary reflections of layered materials can be revealed more clearly by using deconvolution algorithms
Main Factors Influencing the Gut Microbiota of Datong Yaks in Mixed Group
No full textSIMPLE SUMMARY: This study examined the differences and similarities in gut microbial diversity and ecological assembly processes of Datong yaks, including domestic males and females and wild males, which were fed together on the Qinghai-Tibet Plateau in a mixed group. The results revealed that mixed grouping could influence the gut microbiota of these three groups of yaks and improve the gut microbial diversity of domestic females. The findings of this study can help to understand the effects of mixed grouping on the gut microbiota of livestock on the Qinghai-Tibet Plateau and improve the production of Datong yaks. ABSTRACT: The Datong yak (Bos grunniens) is the first artificial breed of yaks in the world and has played an important role in the improvement of domestic yak quality on the Qinghai-Tibet Plateau. The Datong yak breeding farm in the Qinghai province of China is the main place for the breeding and feeding of Datong yaks. It hosts domestic Datong yaks and wild male yaks, mainly in mixed groups. Different managements have different effects on livestock. The gut microbiota is closely related to the health and immunity of Datong yaks, and mixed grouping can affect the composition and diversity of the gut microbiota of Datong yaks. To reveal the effects of mixed grouping on the gut microbiota of Datong yaks and wild yaks and identify the main dominant factors, we compared the gut microbial diversities of domestic males and females and wild males based on 16S rRNA V3–V4 regions using fresh fecal samples. The data showed significant differences in the gut microbial diversity of these three groups, and the α-diversity was the highest in wild males. Different factors influence the gut microbiota, and the main influencing factors were different in different groups, including sex differences, host genetics, and physical interactions. We also compared ecological assembly processes in the three groups. The results showed that mixed grouping contributed to the improvement of gut microbial diversity in domestic females. Our study provides effective and feasible suggestions for the feeding and management of the Datong yaks
Complete mitochondrial genome of Equus caballus (Datong horse)
No full textDatong horse processes a muscular physique with high tolerance to extensive management and adapts well to high altitude conditions in Qinghai, China. In this study, the whole mitochondrial genome sequence of E. caballus determined using next-generation sequencing data was 16,654 bp in length, consisting of 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and a non-coding control region. Notably, there was one tandem repeat with 21 ‘CACCTGTG’ located in the control region. The base composition of the genome was A (32.3%), C (28.6%), G (13.3%), and T (25.8%), with an A + T content of 58.1%. Molecular phylogeny demonstrated that E. caballus was more closely related to a breed from central Asia and processed distinct relationships with some Chinese breeds. This work characterized the mitogenome of E. caballus (Datong horse breed) and present significant genetic information for this valuable specimen
The temporal variations of the annual runoff and sediment load at Yichang and Datong.
No full textThe temporal variations of the annual runoff and sediment load at Yichang and Datong.</p
Copy Number Variations of KLF6 Modulate Gene Transcription and Growth Traits in Chinese Datong Yak (Bos Grunniens)
No full textCopy number variation (CNV) is a significant marker of the genetic and phenotypic diversity among individuals that accounts for complex quantitative traits of phenotype and diseases via modulating gene dosage and disrupting coding regions in the genome. Biochemically, Kruppel-like factor 6 (KLF6) genes plays a significant role in the regulation of cell differentiation and proliferation and muscle development. The aim of this study was to detect the distributions of KLF6 copy number variations (CNVs) in five breeds of domestic yak and to explore their effect on growth traits and gene expression. The data were analyzed by real-time quantitative PCR (qPCR). Our results elucidated that a decreased CNV in the KLF6 gene is more highly associated (p < 0.05) with various growth traits than increased or normal CNVs in six-month-old and five-year-old Datong yak. Nevertheless, negative correlations between the DNA copy number and KLF6 gene expression were observed in the skeletal muscle of adult Datong yak. These results suggest that CNVs of the KLF6 gene could be crucial genomic markers for growth phenotypes of Chinese Datong yak breeds and this finding constitutes the first evidence of the biological role of KLF6 CNVs in Chinese Datong yak breeds
Mann-Kendall values of the flood season runoff at the following stations: (A) Yichang, (B) Hankou and (C) Datong.
No full textMann-Kendall values of the flood season runoff at the following stations: (A) Yichang, (B) Hankou and (C) Datong.</p
Mann-Kendall values of the dry season runoff at the following stations: (A) Yichang, (B) Hankou and (C) Datong.
No full textMann-Kendall values of the dry season runoff at the following stations: (A) Yichang, (B) Hankou and (C) Datong.</p
Ecological Risk and Human Health Assessment of Heavy Metals in Sediments of Datong Lake
No full textHeavy metal pollution of lake sediments is one of the prominent ecological and environmental problems worldwide, and it is of great significance to conduct research on heavy metal pollution in lake sediments to protect the ecological environment, safeguard human health, and promote sustainable development. As an integral part of Dongting Lake, Datong Lake holds a crucial ecological position. More than 10 years ago, due to a series of factors, including excessive fertilizer application and fishing, the water quality of Datong Lake declined, resulting in varying degrees of contamination by Cd, Mn, and other heavy metals in the sediments. After 2017, Datong Lake began to establish a mechanism for protecting and managing the lake, and its ecological and environmental problems have been significantly improved. To clarify the current situation of heavy metal contamination in the sediments of Datong Lake, 15 sediment samples were collected from the lake, and the contents of soil heavy metals Cd, As, Pb, Cr, Cu, Mn, Ni, and Zn were determined. A Monte Carlo simulation was introduced to carry out the ecological and human health risk evaluation of the sediments in the study area to overcome the problem of low reliability of the results of ecological and human health risk evaluation due to the randomness and incompleteness of the environmental data as well as the differences in the human body parameters. The results and conclusions show that (1) the average values of Cd, Pb, Cr, Cu, Mn, Ni, and Zn contents in the sediments of Datong Lake are higher than the background values of soil elements in the sediments of Dongting Lake, and the average values of As contents of heavy metals are lower than the background values of the soil, and the heavy metal contamination in the sediments in the study area is dominated by slight contamination, and the possibility of point-source contamination is slight. (2) The results of both the Geo-accumulation index and Enrichment factor evaluation showed that the degree of heavy metal contamination of sediments was Ni > Cu > Cr > Mn > Cd > Pb > Zn > As. (3) The average value of the single ecological risk index of heavy metal elements, in descending order, was as follows: Cd > As > Pb > Cu > Ni > Cr > Zn > Mn; all the heavy metal elements were at the level of light pollution, and the average value of the comprehensive ecological risk index was 32.83, which is a slight ecological risk level. (4) Both non-carcinogenic and carcinogenic risks for all populations in the study area remain low following heavy metal exposure via ingestion and dermal pathways. Ecological and health risk assessments identified As and Cd as exhibiting significantly higher sensitivity than other heavy metals. Consequently, continuous monitoring and source-tracking of these elements are recommended to safeguard long-term ecological integrity and public health in the region
Morphometric Evaluation of Spermatogenic Cells and Seminiferous Tubules and Exploration of Luteinizing Hormone Beta Polypeptide in Testis of Datong Yak
No full textHistological examination of testes is essential for understanding infertility, sex development, and growth. Therefore, to understand the histomorphology of testes at different developmental stages, we performed hematoxylin and eosin staining of Yak testis. Our results revealed that the diameters of spermatogenic cells and their nuclei were significantly larger (p < 0.05) in the testis at six years compared to at six and 18 months. No significant difference was noted between 30 months and six years. The study was designed to compare the expression profile of LHB in Datong yak. The expression pattern of LHB was explored using quantitative PCR, semi-quantitative PCR, molecular bioinformatic, and Western blot analysis. Our observations indicated that expression of LHB was significantly higher (p < 0.05) in the testis of Datong yak. Western blotting indicated that the molecular mass of LHB protein was 16 kDa in yak. The protein encoded by yak LHB included conserved cysteine-knot domain regions. The high expression of LHB in testis indicated that LHB may be vital for the development of male gonads and the fertility of Datong yak
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