50 results on '"Yang, Tianyuan"'
Search Results
2. Parental support for sexual orientation and demoralization syndrome in Chinese gay men: the mediating role of sexual orientation concealment and relational self-esteem.
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Li, Tiezhu, Gong, Yanquan, Yang, Tianyuan, Ouyang, Zheyu, and Li, Fang
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SEXUAL orientation ,GAY men ,PUBLIC health ,MEDICAL sciences ,SELF-esteem ,MENTAL health - Abstract
Chinese gay men may have high levels of demoralization syndrome, and perceived support from parents for sexual orientation may have an essential impact on an individual's mental health. However, there are few studies on the relationship and mechanism between parental support for sexual orientation and demoralization syndrome among gay men. Therefore, this study aims to examine the relationship between parental support for sexual orientation and demoralization syndrome among Chinese gay men, as well as the chain mediating mechanisms of sexual orientation concealment and relational self-esteem between the two. 405 Chinese gay men recruited via the Internet were assessed by self-reported scales measuring parental support for sexual orientation, sexual orientation concealment, relational self-esteem, and demoralization syndrome. The research results show that parental support for sexual orientation was significantly negatively correlated with demoralization syndrome among Chinese gay men. Sexual orientation concealment significantly mediated the relationship between parental support for sexual orientation and demoralization syndrome, and sexual orientation concealment and relational self-esteem had a significant chain mediation effect between parental support for sexual orientation and demoralization syndrome. Additionally, relational self-esteem also significantly mediated the relationship between the two. The results suggest that parental support for sexual orientation may be a protective factor against demoralization syndrome among Chinese gay men. Parental support for sexual orientation is associated with reduced demoralization syndrome symptoms through lower sexual orientation concealment and higher relational self-esteem. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Realizing Augmenting Technology–Human Symbiosis: A Qualitative Examination from the Organizational Learning Perspective.
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Yang, Tianyuan and Jiang, Jianwu
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ARTIFICIAL intelligence ,HUMAN-computer interaction ,SYSTEMS theory ,INDUSTRIAL relations ,CUSTOMER services ,ORGANIZATIONAL learning - Abstract
Integrating intelligent machines into human work represents a critical challenge that requires effective cooperation between humans and technology. This article explores the concept of augmenting technology-human symbiosis and investigates the role of organizational learning in facilitating this cooperation. The aim of this qualitative study is to examine the intentions, dimensions, and manifestations of augmenting technology-human symbiosis in work processes and identify pathways to its realization. Data was collected through interviews with 21 senior managers in technical service organizations in China. The study reveals four key aspects of effective symbiosis: coexistence, evolution, asymmetry, and reciprocity. Additionally, it delves into five principles of organizational learning that facilitate optimal symbiosis: team learning, shared vision, personal mastery, mental models, and systems thinking. These findings provide valuable insights for promoting integration and cooperation between augmenting technologies and humans, contributing to the fields of human-computer cooperation and organizational learning. By adopting an organizational learning perspective, this research enhances our understanding of augmenting technology-human symbiosis and paves the way for further research and practical implementation of intelligent machines. [ABSTRACT FROM AUTHOR]
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- 2024
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4. LUX ARRHYTHMO links CBF pathway and jasmonic acid metabolism to regulate cold tolerance of tea plants.
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Wang, Yanli, Tong, Wei, Li, Fangdong, Samarina, Lidiia, Li, Penghui, Yang, Tianyuan, Zhang, Zhaoliang, Yi, Lianghui, Zhai, Fei, Wang, Xinchao, and Xia, Enhua
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- 2024
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5. Internalized Homonegativity and Demoralization Syndrome in Chinese Gay Men: The Mediating Role of Sexual Orientation Concealment and Sense of Self.
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Li, Tiezhu, Li, Fang, Yang, Tianyuan, Dai, Xinli, and Gong, Yanquan
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SEXUAL orientation ,GAY men ,SELF ,SEXUAL minorities ,HOMOPHOBIA ,SYNDROMES - Abstract
Introduction: Chinese gay men face substantial stress, such as internalized homonegativity, and may have high levels of demoralization syndrome. However, few studies have examined the relationship between the two. This study aimed to investigate the relationship and the mediating mechanism between internalized homonegativity and demoralization syndrome in Chinese gay men. Methods: From March to May 2022, 319 Chinese gay men were recruited nationwide through the Internet (mean age = 23.99, SD = 4.23). The researchers used the internalized homonegativity scale, the sexual orientation concealment scale, the sense of self scale, and the short version of the demoralization scale for the measurements. Results: Sense of self plays a mediating role between internalized homonegativity and demoralization (standardized estimate = 0.104, 95% CI [0.004, 0.205]). Sexual orientation concealment and sense of self play a sequential mediating role between internalized homonegativity and demoralization (standardized estimate = 0.178, 95% CI [0.113, 0.258]). Internalized homonegativity contributes to increased demoralization among gay men through the increment of sexual orientation concealment and the reduction of sense of self. Conclusions: Internalized homonegativity may be a risk factor for demoralization syndrome among Chinese gay men. Internalized homonegativity is associated with increased demoralization syndrome through increased sexual orientation concealment and decreased sense of self. Policy Implications: Policymakers can formulate some corresponding laws, such as ensuring that sexual minorities are treated equally with heterosexuals in terms of studying and finding jobs in order to reduce the sources of internalized homonegativity formation and the symptoms of demoralization syndrome. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Human Motion Enhancement and Restoration via Unconstrained Human Structure Learning.
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He, Tianjia, Yang, Tianyuan, and Konomi, Shin'ichi
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MOTION capture (Human mechanics) ,LEARNING ,HUMAN skeleton ,MOTION detectors ,SPORTS sciences ,INDUSTRIAL applications - Abstract
Human motion capture technology, which leverages sensors to track the movement trajectories of key skeleton points, has been progressively transitioning from industrial applications to broader civilian applications in recent years. It finds extensive use in fields such as game development, digital human modeling, and sport science. However, the affordability of these sensors often compromises the accuracy of motion data. Low-cost motion capture methods often lead to errors in the captured motion data. We introduce a novel approach for human motion reconstruction and enhancement using spatio-temporal attention-based graph convolutional networks (ST-ATGCNs), which efficiently learn the human skeleton structure and the motion logic without requiring prior human kinematic knowledge. This method enables unsupervised motion data restoration and significantly reduces the costs associated with obtaining precise motion capture data. Our experiments, conducted on two extensive motion datasets and with real motion capture sensors such as the SONY (Tokyo, Japan) mocopi, demonstrate the method's effectiveness in enhancing the quality of low-precision motion capture data. The experiments indicate the ST-ATGCN's potential to improve both the accessibility and accuracy of motion capture technology. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Detecting Leadership Opportunities in Group Discussions Using Off-the-Shelf VR Headsets.
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Gu, Chenghao, Chen, Jiadong, Zhang, Jiayi, Yang, Tianyuan, Liu, Zhankun, and Konomi, Shin'ichi
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NONVERBAL communication ,VIRTUAL communications ,HEADSETS ,VIRTUAL reality ,LEADERSHIP - Abstract
The absence of some forms of non-verbal communication in virtual reality (VR) can make VR-based group discussions difficult even when a leader is assigned to each group to facilitate discussions. In this paper, we discuss if the sensor data from off-the-shelf VR devices can be used to detect opportunities for facilitating engaging discussions and support leaders in VR-based group discussions. To this end, we focus on the detection of suppressed speaking intention in VR-based group discussions by using personalized and general models. Our extensive analysis of experimental data reveals some factors that should be considered to enable effective feedback to leaders. In particular, our results show the benefits of combining the sensor data from leaders and low-engagement participants, and the usefulness of specific HMD sensor features. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Glufosinate‐ammonium causes liver injury in zebrafish by blocking the Nrf2 pathway.
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Kou, Yuhong, Chen, Yongping, Feng, Tongtong, Chen, Luomeng, Wang, Hui, Sun, Ning, Zhao, Shuping, Yang, Tianyuan, Jiao, Wenjing, Feng, Guofeng, Fan, Honggang, and Zhao, Yuan
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LIVER injuries ,NUCLEAR factor E2 related factor ,GLUTATHIONE peroxidase ,BRACHYDANIO ,NON-target organisms ,ASPARTATE aminotransferase ,REACTIVE oxygen species - Abstract
Glufosinate‐ammonium (GLA) is a widely used herbicide, but less research has been done on its harmful effects on non‐target organisms, especially aquatic organisms. In this study, 600 adult zebrafish were exposed to different concentration of GLA (0, 1.25, 2.5, 5, 10, and 20 mg/L) for 7 days, and the livers were dissected on the eighth day to examine the changes in liver structure, function, oxidative stress, inflammation, apoptosis, and Nrf2 pathway, and finally to clarify the mechanism of GLA induced liver injury in zebrafish. The levels of alanine aminotransferase, aspartate aminotransferase, reactive oxygen species, malondialdehyde, inflammatory factors (IL‐6 and TNF‐α), and caspase‐3 gradually increased, while the levels of superoxide dismutase, catalase, glutathione, and glutathione peroxidase gradually decreased with the increase of GLA concentration. The Nrf2 pathway was activated at low concentrations (1.25–5 mg/L) and significantly inhibited at high concentrations (10 and 20 mg/L). These results suggested that GLA could cause oxidative stress, inflammation, and apoptosis in zebrafish liver. Therefore, GLA can cause liver injury in zebrafish, and at high concentrations, the inhibition of Nrf2 pathway is one of the important causes of liver injury. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Adaptive Meta Transfer Learning with Efficient Self-Attention for Few-Shot Bearing Fault Diagnosis.
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Zhao, Jun, Tang, Tang, Yu, Ying, Wang, Jingwei, Yang, Tianyuan, Chen, Ming, and Wu, Jie
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MACHINE learning ,LEARNING strategies ,FAULT diagnosis - Abstract
The success of these meta-learning methods in few-shot bearing fault diagnosis depends strictly on the assumption that the meta-training set and the meta-testing set share the same distribution, which inevitably leads to undesirable performance degradation in varying working conditions. In this paper, we propose a novel Adaptive Siamese-based Meta Transfer Learning Networks (ASTN) for cross-domain fault diagnosis with limited data. Our algorithm learns meta-knowledge from episodic metric meta-learning and further adapts the prior experience to the target domain with a transfer learning strategy. The experiment results demonstrate that our proposed approach outperforms a series of existing meta-learning methods with fewer auxiliary samples. Meanwhile, with the increment of the complexity in the meta-training set, the proposed ASTN achieves good cross-domain generalization. [ABSTRACT FROM AUTHOR]
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- 2023
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10. An Efficient Channel Imbalance Estimation Method Based on Subadditivity of Linear Normed Space of Sub-Band Spectrum for Azimuth Multichannel SAR.
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Xu, Zongxiang, Lu, Pingping, Cai, Yonghua, Li, Junfeng, Yang, Tianyuan, Wu, Yirong, and Wang, Robert
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CHANNEL estimation ,NORMED rings ,VECTOR spaces ,AZIMUTH ,SYNTHETIC aperture radar - Abstract
Azimuth multichannel (AMC) technology is one of the mainstream technical approaches to realize high-resolution wide-swath (HRWS) imaging. It has been successfully applied to several synthetic aperture radar (SAR) satellites in orbit. However, the inevitable imbalance between channels can seriously affect the azimuth reconstruction spectrum, introducing ghost targets into the final imaging results and degrading the SAR image quality. In order to address this issue, this paper proposes a channel imbalance estimation method based on minimizing the sum of the sub-band norm (MSSBN) for the reconstructed azimuth spectrum. First, the amplitude imbalance is calibrated in the range-Doppler domain. Then, the echo in each channel with phase imbalances is reconstructed by filters separately and converted to the range-Doppler domain. Finally, the global optimization algorithm is used to find the phase error of each channel so that the reconstructed postcompensation spectrum has the smallest sub-band spectrum norm sum. By two-dimensional blocking, this method can also estimate the space-varying phase imbalance in the range dimension and the time-varying phase imbalance in the azimuth dimension. Experimental results using simulated and actual AMC SAR data from the GF-3 system validate the proposed algorithm's high estimation accuracy and excellent computational efficiency. [ABSTRACT FROM AUTHOR]
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- 2023
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11. Pyrrolizidine-producing weeds in tea gardens as an indicator of alkaloids in tea.
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Jiao, Weiting, Wang, Luyao, Zhu, Lei, Shen, Tingting, Shi, Taozhong, Zhang, Ping, Wang, Chen, Chen, Hongping, Wu, Xiangwei, Yang, Tianyuan, Li, Qing X., and Hua, Rimao
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WEEDS ,PYRROLIZIDINES ,TEA ,GARDENS ,SOIL sampling ,ALKALOIDS - Abstract
Pyrrolizidine alkaloids (PAs) can be transferred between plants via soil. Indicators of PAs in tea products are useful for tea garden management. In the present work a total of 37 weed species, 37 weed rhizospheric soils and 24 fresh tea leaf samples were collected from tea gardens, in which PAs were detected in 35 weeds species, 21 soil samples and 10 fresh tea leaves samples. In Shexian tea garden, 12.9 μg/kg of intermedine (Im) in one bud plus three leaves, 1.40 and 14.6 μg/kg of intermedine-N-oxide (ImNO) in one bud plus two leaves and one bud plus three leaves were detected, which were transferred from the PA-producing weeds via soil. However, no PAs were detected in fresh tea leaves collected from Langxi tea garden. The results indicated that synthesis of PAs in weeds and their transfer through the weed-soil-fresh tea leaf route varied with soil environments in different tea gardens. [ABSTRACT FROM AUTHOR]
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- 2023
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12. Haem Oxygenase 1 is a potential target for creating etiolated/albino tea plants (Camellia sinensis) with high theanine accumulation.
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Chen, Ziping, Lin, Shijia, Chen, Tingting, Han, Mengxue, Yang, Tianyuan, Wang, Yan, Bao, Shilai, Shen, Zhougao, Wan, Xiaochun, and Zhang, Zhaoliang
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THEANINE ,TEA ,HEME ,AMINO acid sequence ,ALBINISM - Abstract
Theanine content is highly correlated with sensory quality and health benefits of tea infusion. The tender shoots of etiolated and albino tea plants contain higher theanine than the normal green tea plants and are valuable materials for high quality green tea processing. However, why these etiolated or albino tea plants can highly accumulate theanine is largely unknown. In this study, we observed an Arabidopsis etiolated mutant hy1–100 (mutation in Haem Oxygenase 1 , HO1) that accumulated higher levels of glutamine (an analog of theanine). We therefore identified CsHO1 in tea plants and found CsHO1 is conserved in amino acid sequences and subcellular localization with its homologs in other plants. Importantly, CsHO1 expression in the new shoots was much lower in an etiolated tea plants 'Huangkui' and an albino tea plant 'Huangshan Baicha' than that in normal green tea plants. The expression levels of CsHO1 were negatively correlated with theanine contents in these green, etiolated and albino shoots. Moreover, CsHO1 expression levels in various organs and different time points were also negatively correlated with theanine accumulation. The hy1–100 was hypersensitive to high levels of theanine and accumulated more theanine under theanine feeding, and these phenotypes were rescued by the expression of CsHO1 in this mutant. Transient knockdown CsHO1 expression in the new shoots of tea plant using antisense oligonucleotides (asODN) increased theanine accumulation. Collectively, these results demonstrated CsHO1 negatively regulates theanine accumulation in tea plants, and that low expression CsHO1 likely contributes to the theanine accumulation in etiolated/albino tea plants. [ABSTRACT FROM AUTHOR]
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- 2023
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13. Theanine, a tea-plant-specific non-proteinogenic amino acid, is involved in the regulation of lateral root development in response to nitrogen status.
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Chen, Tingting, Lin, Shijia, Chen, Ziping, Yang, Tianyuan, Zhang, Shupei, Zhang, Jinsong, Xu, Guohua, Wan, Xiaochun, and Zhang, Zhaoliang
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THEANINE ,ROOT development ,AMINO acids ,GLUTAMINE synthetase ,NITROGEN deficiency ,PLANT metabolites ,REACTIVE oxygen species ,CELL division - Abstract
Glutamine synthetase type I (GSI)-like proteins are proposed to mediate nitrogen signaling and developmental fate by synthesizing yet unidentified metabolites. Theanine, the most abundant non-proteinogenic amino acid in tea plants, is the first identified metabolite synthesized by a GSI-like protein (CsTSI) in a living system. However, the roles of theanine in nitrogen signaling and development are little understood. In this study we found that nitrogen deficiency significantly reduced theanine accumulation and increased lateral root development in tea plant seedlings. Exogenous theanine feeding significantly repressed lateral root development of seedlings of tea plants and the model plant Arabidopsis. The transcriptomic analysis revealed that the differentially expressed genes in the roots under theanine feeding were enriched in the apoplastic pathway and H
2 O2 metabolism. Consistently, theanine feeding reduced H2 O2 levels in the roots. Importantly, when co-treated with H2 O2 , theanine abolished the promoting effect of H2 O2 on lateral root development in both tea plant and Arabidopsis seedlings. The results of histochemical assays confirmed that theanine inhibited reactive oxygen species accumulation in the roots. Further transcriptomic analyses suggested the expression of genes encoding enzymes involved in H2 O2 generation and scavenging was down- and upregulated by theanine, respectively. Moreover, the expression of genes involved in auxin metabolism and signaling, cell division, and cell expansion was also regulated by theanine. Collectively, these results suggested that CsTSI-synthesized theanine is likely involved in the regulation of lateral root development, via modulating H2 O2 accumulation, in response to nitrogen levels in tea plants. This study also implied that the module consisting of GSI-like protein and theanine-like metabolite is probably conserved in regulating development in response to nitrogen status in plant species. [ABSTRACT FROM AUTHOR]- Published
- 2023
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14. CsGDH2.1 negatively regulates theanine accumulation in late-spring tea plants (Camellia sinensis var. sinensis).
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Chen, Tingting, Ma, Jingzhen, Li, Huiping, Lin, Shijia, Dong, Chunxia, Xie, Yunxia, Yan, Xiaomei, Zhang, Shupei, Yang, Tianyuan, Wan, Xiaochun, and Zhang, Zhaoliang
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THEANINE ,TEA ,UMAMI (Taste) ,PLANT shoots ,GREEN tea ,PLANT extracts - Abstract
Theanine, a unique and the most abundant non-proteinogenic amino acid in tea plants, endows tea infusion with the umami taste and anti-stress effects. Its content in tea correlates highly with green tea quality. Theanine content in new shoots of tea plants is high in mid-spring and greatly decreases in late spring. However, how the decrease is regulated is largely unknown. In a genetic screening, we observed that a yeast mutant, glutamate dehydrolase 2 (gdh2), was hypersensitive to 40 mM theanine and accumulated more theanine. This result implied a role of CsGDH2s in theanine accumulation in tea plants. Therefore, we identified the two homologs of GDH2, CsGDH2.1 and CsGDH2.2, in tea plants. Yeast complementation assay showed that the expression of CsGDH2.1 in yeast gdh2 mutant rescued the theanine hypersensitivity and hyperaccumulation of this mutant. Subcellular localization and tissue-specific expression showed CsGDH2.1 localized in the mitochondria and highly expressed in young tissues. Importantly, CsGDH2.1 expression was low in early spring, and increased significantly in late spring, in the new shoots of tea plants. These results all support the idea that CsGDH2.1 regulates theanine accumulation in the new shoots. Moreover, the in vitro enzyme assay showed that CsGDH2.1 had glutamate catabolic activity, and knockdown of CsGDH2.1 expression increased glutamate and theanine accumulation in the new shoots of tea plants. These findings suggested that CsGDH2.1-mediated glutamate catabolism negatively regulates theanine accumulation in the new shoots in late spring, and provides a functional gene for improving late-spring green tea quality. [ABSTRACT FROM AUTHOR]
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- 2023
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15. Self-Compassion Contributes to Decreased Hopelessness in Young Gay Men: Two Types of Maladaptive Coping Strategies as Mediators.
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Li, Fang, Liao, Jundong, Liu, Lei, Yang, Tianyuan, Dai, Xinli, and Li, Jie
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GAY men ,DESPAIR ,GAY identity ,YOUNG men ,COMPASSION ,RUMINATION (Cognition) - Abstract
Introduction: Hopelessness is widespread among gay men, and it is of great academic value to identify personal factors that can ameliorate their hopelessness. The objective of this study was to determine whether self-compassion is associated with decreased hopelessness in young gay men, and explore the mediating effects of two types of maladaptive coping strategies (concealment of gay identity and rumination) on this relationship. Methods: In 2020, 370 Chinese young gay men recruited via the Internet were assessed by self-reported scales measuring self-compassion, concealment of gay identity, rumination, and hopelessness. Results: Findings showed that self-compassion was negatively correlated with hopelessness in young gay men. Rumination mediated the relation between self-compassion and hopelessness, and the size of this mediation effect was larger than other mediation effects. Concealment of gay identity and rumination also played a sequential mediating role between self-compassion and hopelessness, but the independent mediation effect of concealment of gay identity was not statistically significant. Conclusion: Self-compassion contributes to decreased hopelessness among young gay men via the reduction of concealment of gay identity and rumination. Policy Implications: Policy makers need to give more support to programs that strengthen individual self-compassion, such as compassion-focused therapy, to effectively reduce hopelessness among young gay men. [ABSTRACT FROM AUTHOR]
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- 2022
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16. Does Self-Concept Clarity Relate to Depressive Symptoms in Chinese Gay Men? The Mediating Effects of Sexual Orientation Concealment and Gay Community Connectedness.
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Li, Fang, Liao, Jundong, Sun, Xianlin, Yang, Tianyuan, Li, Tiezhu, Wang, Yibo, and Mei, Yusheng
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GAY community ,GAY men ,MENTAL depression ,HOMOSEXUALITY ,HEALTH of gay men ,SEXUAL orientation ,SELF-perception - Abstract
Introduction: Surveys have shown that Chinese gay men have high levels of depressive symptoms. Self-concept clarity is a critical intrapersonal psychological factor affording the alleviation of depressive symptoms. The objective of this research is to investigate whether self-concept clarity is related to depressive symptoms in gay men within the Chinese context and explore the specific mediation mechanisms of sexual orientation concealment and gay community connectedness. Methods: Data were collected online from 405 Chinese gay men in 2020. Participants were assessed with scales regarding self-concept clarity, sexual orientation concealment, gay community connectedness, and depressive symptoms. Results: Self-concept clarity was negatively correlated with depressive symptoms in Chinese gay men. The relation between self-concept clarity and depressive symptoms was mediated by sexual orientation concealment, and sexual orientation concealment and gay community connectedness also played a sequential mediation effect between self-concept clarity and depressive symptoms. Conclusion: The improvement of self-concept clarity may be one of the foremost concerns for the decrease in depressive symptoms among Chinese gay men. Self-concept clarity is related to reduced depressive symptoms through lower sexual orientation concealment and higher gay community connectedness. Policy Implications: Policy makers should provide more support for organizations and institutions that focus on improving the mental health of Chinese gay men and encourage these organizations and institutions to popularize effective self-adjustment methods (such as improving self-concept clarity) that can help reduce depressive symptoms among gay men. In addition, policy makers should take measures to further enhance social tolerance of homosexuality and provide more gay communication platforms for Chinese gay men. [ABSTRACT FROM AUTHOR]
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- 2022
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17. Tonoplast-Localized Theanine Transporter CsCAT2 May Mediate Theanine Storage in the Root of Tea Plants (Camellia sinensis L.).
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Feng, Lin, Yu, Yongchao, Lin, Shijia, Yang, Tianyuan, Chen, Qi, Liu, Linlin, Sun, Jun, Zheng, Pengcheng, Zhang, Zhaoliang, and Wan, Xiaochun
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THEANINE ,TEA ,PLANT roots ,AMINO acids ,GLUTAMINE ,GLUTAMINE synthetase ,STORAGE - Abstract
Theanine is the component endowing tea infusion with "umami" taste and antidepression benefits. Theanine is primarily synthesized and stored in root in winter and is transported via vascular tissues to the new shoot in spring. However, the mechanism underlying theanine storage in the root of tea plants remains largely unknown. Cationic amino acid transporter 2 (CsCAT2) in tea plants is homologous to glutamine permease 1 (GNP1), the specific glutamine transporter in yeast. In this study, we identified CsCAT2 as an H
+ -dependent theanine transporter with medium affinity for theanine. The result of subcellular localization showed that CsCAT2 was a tonoplast-localized transporter. Importantly, CsCAT2 highly expressed in the root in winter during theanine storage and reduced its expression in the root during theanine transport from root-to-shoot in spring. In addition, CsCAT2 expression in the roots of 5 varieties at four time points during December and April was significant negatively correlated with the capacity of theanine root-to-shoot movement. Taken together, these results suggested that CsCAT2 may mediate theanine storage in the vacuole of root cells and may negatively modulate theanine transport from root to shoot. [ABSTRACT FROM AUTHOR]- Published
- 2021
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18. Theanine Improves Salt Stress Tolerance via Modulating Redox Homeostasis in Tea Plants (Camellia sinensis L.).
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Chen, Ziping, Lin, Shijia, Li, Juan, Chen, Tingting, Gu, Quan, Yang, Tianyuan, and Zhang, Zhaoliang
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THEANINE ,TEA ,TEA extracts ,PROLINE ,GLUTAMINE synthetase ,SALT ,REACTIVE oxygen species ,PLANT shoots - Abstract
Theanine, a unique non-proteinogenic amino acid, is one of the most abundant secondary metabolites in tea. Its content largely determines green tea quality and price. However, its physiological roles in tea plants remain largely unknown. Here, we showed that salt stress significantly increased the accumulation of glutamate, glutamine, alanine, proline, and γ-aminobutyric acid, as well as theanine, in the new shoots of tea plants. We further found that salt stress induced the expression of theanine biosynthetic genes, including CsGOGATs , CsAlaDC , and CsTSI , suggested that salt stress induced theanine biosynthesis. Importantly, applying theanine to the new shoots significantly enhanced the salt stress tolerance. Similar effects were also found in a model plant Arabidopsis. Notably, exogenous theanine application increased the antioxidant activity of the shoots under salt stress, suggested by reduced the reactive oxygen species accumulation and lipid peroxidation, as well as by the increased SOD, CAT, and APX activities and expression of the corresponding genes. Finally, genetic evidence supported that catalase-mediated antioxidant scavenging pathway is required for theanine-induced salt stress tolerance. Taken together, this study suggested that salt stress induces theanine biosynthesize in tea plants to enhance the salt stress tolerance through a CAT-dependent redox homeostasis pathway. [ABSTRACT FROM AUTHOR]
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- 2021
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19. Protective Effects of Low-Dose Alcohol against Acute Stress-Induced Renal Injury in Rats: Involvement of CYP4A/20-HETE and LTB4/BLT1 Pathways.
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Chen, Yongping, Yang, Haotian, Yang, Tianyuan, Zhang, Haiyang, Zhao, Yuan, Li, Lin, and Fan, Honggang
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- 2021
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20. An Adaptive Radar Signal Processor for UAVs Detection With Super-Resolution Capabilities.
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Yang, Tianyuan, De Maio, Antonio, Zheng, Jibin, Su, Tao, Carotenuto, Vincenzo, and Aubry, Augusto
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This paper is focused on the detection and resolution of Unmanned Aerial Vehicles (UAVs) via a multi-channel phased-array radar with emphasis on the challenging situation where multiple targets are unresolved in the range-Doppler domain and closely spaced in angle. An adaptive processor is devised which, after triggering a detection in a given range-Doppler cell, implements a binary decision about the presence of a single or multiple targets. In the former situation, the plain monopulse algorithm is used to estimate the target azimuth whereas, in the latter case, a super-resolution technique is activated to get the angular parameters of the UAVs. The performance of the signal processor is assessed both on simulated and on measured data (endowed by ground-truth) collected by a 12-channel phased-array radar operating in the C-band. The results highlight the capabilities of the architecture to detect the presence of targets, to discriminate the single from the multiple targets scenario, and to resolve the UAVs in angle domain when they are unresolved in range and Doppler. [ABSTRACT FROM AUTHOR]
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- 2021
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21. The tea plant CsLHT1 and CsLHT6 transporters take up amino acids, as a nitrogen source, from the soil of organic tea plantations.
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Li, Fang, Dong, Chunxia, Yang, Tianyuan, Bao, Shilai, Fang, Wanping, Lucas, William J., and Zhang, Zhaoliang
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AMINO acids ,TEA ,PLANTATIONS ,NITROGEN in soils ,GLUTAMIC acid - Abstract
Organic tea is more popular than conventional tea that originates from fertilized plants. Amino acids inorganic soils constitute a substantial pool nitrogen (N) available for plants. However, the amino-acid contents in soils of tea plantations and how tea plants take up these amino acids remain largely unknown. In this study, we show that the amino-acid content in the soil of an organic tea plantation is significantly higher than that of a conventional tea plantation. Glutamate, alanine, valine, and leucine were the most abundant amino acids in the soil of this tea plantation. When
15 N-glutamate was fed to tea plants, it was efficiently absorbed and significantly increased the contents of other amino acids in the roots. We cloned seven CsLHT genes encoding amino-acid transporters and found that the expression of CsLHT1, CsLHT2, and CsLHT6 in the roots significantly increased upon glutamate feeding. Moreover, the expression of CsLHT1 or CsLHT6 in a yeast amino-acid uptake-defective mutant, 22∆10α, enabled growth on media with amino acids constituting the sole N source. Amino-acid uptake assays indicated that CsLHT1 and CsLHT6 are H+ -dependent high- and low-affinity amino-acid transporters, respectively. We further demonstrated that CsLHT1 and CsLHT6 are highly expressed in the roots and are localized to the plasma membrane. Moreover, overexpression of CsLHT1 and CsLHT6 in Arabidopsis significantly improved the uptake of exogenously supplied15 N-glutamate and15 N-glutamine. Taken together, our findings are consistent with the involvement of CsLHT1 and CsLHT6 in amino-acid uptake from the soil, which is particularly important for tea plants grown inorganic tea plantations. [ABSTRACT FROM AUTHOR]- Published
- 2021
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22. Accurate Detection and Localization of Unmanned Aerial Vehicle Swarms-Enabled Mobile Edge Computing System.
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Zheng, Jibin, Yang, Tianyuan, Liu, Hongwei, Su, Tao, and Wan, Liangtian
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Unmanned aerial vehicle (UAV) swarms-enabled mobile edge computing system can be deployed in critical industrial zones for monitoring. Meanwhile, its malicious use may bring great threat to the security, and the accurate detection, and localization are important. UAV swarms show characteristics of the high density, small radar cross section, far range, and time-varying motion, and have posed formidable challenges to the accurate detection and localization. In this article, the accurate detection and localization of UAV swarms are investigated, and an effective method is proposed based on the Dechirp-keystone transform, and frequency-selective reweighted trace minimization. It inherits high robustness of the coherent long-time integration technique and superresolution of the gridless sparse technique. Mathematical analyzes and numerical simulations validate its superiorities in accurate detection and localization of UAV swarms. [ABSTRACT FROM AUTHOR]
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- 2021
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23. Genome-wide analyses and expression patterns under abiotic stress of LAC gene family in pear (Pyrus bretschneideri).
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Lu, Chunyi, Yang, Tianyuan, Zhang, Yiwu, Miao, Xingchen, Jin, Cong, and Xu, Xiaoyong
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ABIOTIC stress ,GENE families ,PLANT cell walls ,CHROMOSOME duplication ,LACCASE ,DROUGHT management - Abstract
Plant laccases are copper-containing glycoproteins oxidizing monolignol, which is a key regulator for lignin polymerization and deposition in plant cell walls. In plants, the LAC gene family has been identified and functionally characterized in Arabidopsis, rice, and other plant species. Whereas, no systematic analysis of LAC genes was explored in pear (Pyrus bretschneideri), especially their biological roles in stress responses. In this study, a total of 40 P. bretschneideri LACs (PbLACs) were identified from the pear genome, among which 32 PbLACs members were distributed on 14 chromosomes, and 8 PbLACs were mapped onto scaffold contigs. Subsequently, the chromosome localizations, gene structures, conserved domains, gene duplication were analyzed comprehensively and bioinformatically. Phylogenetic analysis demonstrated that the PbLACs were classified into seven groups. Synteny analysis exhibited that whole-genome duplication (WGD)/segmental duplication was essential for the expansion of PbLAC family. In detail, the 26 PbLACs duplicated gene pairs were taken place at the two WGD events. Further, our results showed that purifying selection presented as the primary force to drive the evolution of PbLACs. Notably, the transcriptomic data were used for exploring the biological roles of PbLACs in response to abiotic stresses (cold, drought, and salt) in pear. We found that the expression of certain PbLACs was significantly induced by drought, cold or salt treatments, suggesting that these PbLACs are potentially key genes for further functional characterization in pear in the future. Taken together, our results not only contribute to an enhanced understanding of the evolutional complexity of PbLAC gene family but also provide a good platform for functional studies of PbLAC genes in response to various abiotic stresses. [ABSTRACT FROM AUTHOR]
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- 2021
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24. Efficient Data Transmission Strategy for IIoTs With Arbitrary Geometrical Array.
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Zheng, Jibin, Yang, Tianyuan, Liu, Hongwei, and Su, Tao
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Various kinds of data are generated from industrial Internet of Things, and these data can be applied for connecting production equipment, identifying and locating items, etc. These data should be forwarded to the decision center for further analyses, especially in wartime. Thus, the channel status information (CSI) for industrial big data transmission has to be acquired. In this article, we develop a system architecture for industrial big data (BD) transmission based on radar-communication integration with arbitrary geometrical array. The traditional channel estimation method, which usually utilizes the regular antenna array to estimate the CSI, cannot be applied to the arbitrary geometrical array. Here, we use the manifold separation technique to transform the complex array configuration into regular array and the downlink channel covariance matrix is estimated by exploiting the frequency calibration technique when the uplink channel covariance matrix is received. The computational complexity for the proposed method and other state-of-the-art methods are analyzed. The simulation results prove that the proposed method can achieve excellent estimation performance for its application in radar-communication integration. [ABSTRACT FROM AUTHOR]
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- 2021
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25. Transcriptome analysis provides insights into the molecular bases in response to different nitrogen forms-induced oxidative stress in tea plant roots (Camellia sinensis).
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Chen, Ziping, Li, Huiping, Yang, Tianyuan, Chen, Tingting, Dong, Chunxia, Gu, Quan, and Cheng, Xunmin
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OXIDATIVE stress ,PLANT roots ,TEA ,PROANTHOCYANIDINS ,ABSCISIC acid ,HYDROGEN peroxide - Abstract
Previous studies have suggested that the maintenance of redox homeostasis is essential for plant growth. Here we investigated how redox homeostasis and signalling is modulated in response to different nitrogen (N) forms in tea plant roots. Our results showed that both N deficiency and nitrate (NO
3 – ) can trigger the production of hydrogen peroxide and lipid peroxidation in roots. In contrast, these responses were not altered by NH4 + . Further, N deficiency and NO3 – -triggered redox imbalance was re-established by increased of proanthocyanidins (PAs) and glutathione (GSH), as well as upregulation of representative antioxidant enzyme activities and genes. To further explore the molecular bases of these responses, comparative transcriptome analysis was performed, and redox homeostasis-associated differentially expressed genes (DEGs) were selected for bioinformatics analysis. Most of these genes were involved in the flavonoid biosynthesis, GSH metabolism and the antioxidant system, which was specifically altered by N deficiency or NO3 – . Moreover, the interplay between H2 O2 (generated by RBOH and Ndufab1) and hormones (including abscisic acid, auxin, cytokinin and ethylene) in response to different N forms was suggested. Collectively, the above findings contribute to an understanding of the underlying molecular mechanisms of redox homeostasis and signalling in alleviating oxidative stress in tea plant roots. Nitrogen availability has a major impact on tea productivity; however, how tea plants respond to different N forms remain unknown. Our findings reveal the molecular mechanisms of redox homeostasis and signalling in alleviating oxidative stress induced by N deficiency or NO3 – . This paper provides candidate redox-related genes for researchers investigating abiotic stress in tea plants. [ABSTRACT FROM AUTHOR]- Published
- 2020
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26. Thermal Exchange and Skid Resistance of Chip Seal with Various Aggregate Types and Morphologies.
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Wei, Minghua, Wu, Shaopeng, Cui, Peide, Yang, Tianyuan, and Lv, Yang
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SKID resistance ,BASIC oxygen furnaces ,MAINTENANCE ,ASPHALT pavements ,INDUSTRIAL wastes - Abstract
Steel slag, the by-product of steelmaking, is a desirable alternative material for natural aggregate. However, there are few studies applying steel slag in the preventive maintenance of asphalt pavements, especially chip seal. The main objective of this study is to explore the feasibility of applying steel slag in chip seal and the effect of steel slag on the thermal exchange and aggregate retention properties. Furthermore, the surface features, including texture depth and skid resistance. of chip seal were also evaluated. The results show that the thermal exchange performances of chip seal vary with aggregate types. The ranking of the chip seal samples according to the cooling rate places ferrochromium (FER) slag as the fastest and basic oxygen furnace (BOF) slag as the slowest, with the basalt (BS) falling in between. The use of FER slag can make the chip seal resume traffic about ten minutes earlier than original samples. The skid resistance and texture depth of FER slag meet the requirements of the specification, although they are less than those of ordinary aggregates. Moreover, FER slag has a better aggregate retention performance than BOF slag and BS due to its spherical particles and alkaline surface. The application of steel slag in chip seal can recycle industrial waste, reduce the consumption of natural resources and promote economic pavement maintenance technology. [ABSTRACT FROM AUTHOR]
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- 2020
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27. LncWNT3‐IT affects the proliferation of Sertoli cells by regulating the expression of the WNT3 gene in goat testis.
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He, Lina, He, Qijie, Qiao, Lei, Huang, Siyi, Dai, Zinuo, Yang, Tianyuan, Liu, Lingbin, and Zhao, Zhongquan
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SERTOLI cells ,CELL proliferation ,TESTIS ,FLUORESCENCE in situ hybridization ,WNT proteins ,SPERMATOGENESIS ,GOAT diseases - Abstract
Contents: The proliferation and differentiation ability of testicular Sertoli cells directly affects spermatogenesis and male reproductive development. WNT proteins are involved in the regulation of cell proliferation, differentiation and spermatogenesis. Therefore, to study whether lncRNAs, which regulate the expression of WNT proteins during cell proliferation and differentiation, are worthwhile. In this study, testicular tissue from the Dazu black goat (Capra, goat, Chongqing, China) at neonatal time (less than 7 days old), early puberty time (45 days old) and sexual maturity time (90 days old) at three ages was subjected to high‐throughput sequencing to predict testicular growth and development associated with WNT lncRNA. The final screening of lncWNT3‐IT may be targeted to regulate the expression of WNT3. At the same time, the expression of WNT3 was verified by lncWNT3‐IT by paraffin sectioning, fluorescence in situ hybridization, interference, overexpression, cytotoxicity assay, Western blotting and qPCR. The following results were obtained: lncWNT3‐IT was expressed in the testicular Sertoli cells and played a role in the Sertoli cell cytoplasm. Fluorescence in situ hybridization localization analysis showed that lncWNT3‐IT positively regulated the expression of WNT3, and through cell viability and cell proliferation experiments, it was found that the expression of lncWNT3‐IT assisted in Sertoli cell proliferation. In summary, lncWNT3‐IT can influence the proliferation of Sertoli cells by positively regulating the expression of WNT3. [ABSTRACT FROM AUTHOR]
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- 2020
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28. HAK/KUP/KT family potassium transporter genes are involved in potassium deficiency and stress responses in tea plants (Camellia sinensis L.): expression and functional analysis.
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Yang, Tianyuan, Lu, Xin, Wang, Yan, Xie, Yunxia, Ma, Jingzhen, Cheng, Xunmin, Xia, Enhua, Wan, Xiaochun, and Zhang, Zhaoliang
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TEA growing ,TEA ,HYPOKALEMIA ,FUNCTIONAL analysis ,NON-alcoholic beverages ,CULTIVARS - Abstract
Background: Tea plant is one of the most important non-alcoholic beverage crops worldwide. While potassium (K
+ ) is an essential macronutrient and greatly affects the growth and development of plants, the molecular mechanism underlying K+ uptake and transport in tea plant root, especially under limited-K+ conditions, is still poorly understood. In plants, HAK/KUP/KT family members play a crucial role in K+ acquisition and translocation, growth and development, and response to stresses. Nevertheless, the biological functions of these genes in tea plant are still in mystery, especially their roles in K+ uptake and stress responses. Results: In this study, a total of 21 non-redundant HAK/KUP/KT genes (designated as CsHAKs) were identified in tea plant. Phylogenetic and structural analysis classified the CsHAKs into four clusters (I, II, III, IV), containing 4, 8, 4 and 5 genes, respectively. Three major categories of cis-acting elements were found in the promoter regions of CsHAKs. Tissue-specific expression analysis indicated extremely low expression levels in various tissues of cluster I CsHAKs with the exception of a high root expression of CsHAK4 and CsHAK5, a constitutive expression of clusters II and III CsHAKs, and a moderate cluster IV CsHAKs expression. Remarkably, the transcript levels of CsHAKs in roots were significantly induced or suppressed after exposure to K+ deficiency, salt and drought stresses, and phytohormones treatments. Also notably, CsHAK7 was highly expressed in all tissues and was further induced under various stress conditions. Therefore, functional characterization of CsHAK7 was performed, and the results demostrated that CsHAK7 locates on plasma membrane and plays a key role in K+ transport in yeast. Taken together, the results provide promising candidate CsHAKs for further functional studies and contribute to the molecular breeding for new tea plants varieties with highly efficient utilization of K+ . Conclusion: This study demonstrated the first genome-wide analysis of CsHAK family genes of tea plant and provides a foundation for understanding the classification and functions of the CsHAKs in tea plants. [ABSTRACT FROM AUTHOR]- Published
- 2020
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29. Dexmedetomidine Enhances Autophagy via α2-AR/AMPK/mTOR Pathway to Inhibit the Activation of NLRP3 Inflammasome and Subsequently Alleviates Lipopolysaccharide-Induced Acute Kidney Injury.
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Yang, Tianyuan, Feng, Xiujing, Zhao, Yuan, Zhang, Haiyang, Cui, Hailin, Wei, Mian, Yang, Haotian, and Fan, Honggang
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NLRP3 protein ,ACUTE kidney failure ,DEXMEDETOMIDINE ,INTRAPERITONEAL injections ,PROTEIN kinases ,PROTEIN receptors ,LIPOPOLYSACCHARIDES - Abstract
Background: Acute kidney injury (AKI) is a severe complication of sepsis; however, no effective drugs have been found. Activation of the nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome is a major pathogenic mechanism of AKI induced by lipopolysaccharide (LPS). Autophagy, a process of intracellular degradation related to renal homeostasis, effectively restricts inflammatory responses. Herein, we explored the potential protective mechanisms of dexmedetomidine (DEX), which has confirmed anti-inflammatory effects, on LPS-induced AKI. Methods: AKI was induced in rats by injecting 10 mg/kg of LPS intraperitoneally (i.p.). Wistar rats received intraperitoneal injections of DEX (30 µg/kg) 30 min before an intraperitoneal injection of LPS. Atipamezole (ATI) (250 µg/kg) and 3-methyladenine (3-MA) (15 mg/kg) were intraperitoneally injected 30 min before the DEX injection. Results: DEX significantly attenuated renal injury. Furthermore, DEX decreased activation of the NLRP3 inflammasome and expression of interleukins 1β and 18. In addition, autophagy-related protein and gene analysis indicated that DEX could significantly enhance autophagy. Finally, we verified the pharmacological effects of DEX on the 5′-adenosine monophosphate-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR) pathway. Atip and 3-MA significantly reversed the protective effects of DEX. Conclusions: Our results suggest that the protective effects of DEX were mediated by enhanced autophagy via the α
2 -adrenoreceptor/AMPK/mTOR pathway, which decreased activation of the NLRP3 inflammasome. Above all, we verified the renal protective effects of DEX and offer a new treatment strategy for AKI. [ABSTRACT FROM AUTHOR]- Published
- 2020
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30. Transcriptional regulation of amino acid metabolism in response to nitrogen deficiency and nitrogen forms in tea plant root (Camellia sinensis L.).
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Yang, Tianyuan, Li, Huiping, Tai, Yuling, Dong, Chunxia, Cheng, Xunmin, Xia, Enhua, Chen, Ziping, Li, Fang, Wan, Xiaochun, and Zhang, Zhaoliang
- Subjects
AMINO acid metabolism ,NITROGEN deficiency ,TEA ,TRANSCRIPTOMES ,GLUTAMIC acid - Abstract
Free amino acids, including theanine, glutamine and glutamate, contribute greatly to the pleasant taste and multiple health benefits of tea. Amino acids in tea plants are mainly synthesized in roots and transported to new shoots, which are significantly affected by nitrogen (N) level and forms. However, the regulatory amino acid metabolism genes have not been systemically identified in tea plants. Here, we investigated the dynamic changes of free amino acid contents in response to N deficiency and forms in tea plant roots, and systemically identified the genes associated amino acid contents in individual metabolism pathways. Our results showed that glutamate-derived amino acids are the most dynamic in response to various forms of N and N deficiency. We then performed transcriptomic analyses of roots treated with N deficiency and various forms of N, and differentially expressed amino acid metabolic genes in each pathway were identified. The analyses on expression patterns and transcriptional responses of metabolic genes to N treatments provided novel insights for the molecular basis of high accumulation of theanine in tea plant root. These analyses also identified potential regulatory genes in dynamic amino acid metabolism in tea plant root. Furthermore, our findings indicated that the dynamic expression levels of CsGDH, CsAlaDC, CsAspAT, CsSDH, CsPAL, CsSHMT were highly correlated with changes of amino acid contents in their corresponding pathways. Herein, this study provides comprehensive insights into transcriptional regulation of amino acid metabolism in response to nitrogen deficiency and nitrogen forms in tea plant root. [ABSTRACT FROM AUTHOR]
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- 2020
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31. CsAlaDC and CsTSI work coordinately to determine theanine biosynthesis in tea plants (Camellia sinensis L.) and confer high levels of theanine accumulation in a non‐tea plant.
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Zhu, Biying, Guo, Jiayi, Dong, Chunxia, Li, Fang, Qiao, Siming, Lin, Shijia, Yang, Tianyuan, Wu, Yingling, Bao, Shilai, Lucas, William J., and Zhang, Zhaoliang
- Subjects
TEA ,THEANINE ,PLANTS ,BIOSYNTHESIS ,TEA growing ,PLANT cell culture - Abstract
CsAlaDC, pK7WGF2+pCAMBIA1305-CsAlaDC; CsTSI, pCAMBIA1305+pK7WGF2-CsTSI; CsAlaDC+CsTSI, pCAMBIA1305-CsAlaDC+pK7WGF2-CsTSI. CsAlaDC and CsTSI work coordinately to determine theanine biosynthesis in tea plants (Camellia sinensis L.) and confer high levels of theanine accumulation in a non-tea plant Keywords: Camellia sinensis L.; theanine; CsAlaDC; ethylamine; biosynthesis; CsTSI EN Camellia sinensis L. theanine CsAlaDC ethylamine biosynthesis CsTSI 2395 2397 3 12/03/21 20211201 NES 211201 Tea, the second most popular nonalcoholic beverage consumed worldwide, is favoured by billions of consumers due to its special flavour and numerous health benefits (Higdon and Frei, 2003). [Extracted from the article]
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- 2021
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32. Toxic effects of hydrogen sulfide donor NaHS induced liver apoptosis is regulated by complex IV subunits and reactive oxygen species generation in rats.
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Feng, Xiujing, Zhang, Haiyang, Shi, Mingxian, Chen, Yongping, Yang, Tianyuan, and Fan, Honggang
- Subjects
HYDROGEN sulfide ,REACTIVE oxygen species ,PROTEIN expression ,APOPTOSIS ,LIVER ,RATS - Abstract
In recent years, the protective effect of hydrogensulfide donor sodium hydrosulfide(NaHS) on multiple organs has been widely reported. The study aimed to explorethe effect of commonly used concentration of NaHS on theliver and its potential damage mechanism. Rats divided into 4 groups: control, NaHS I (1 mg/kg), II (3 mg/kg) and III(5 mg/kg) groups, and each group is divided into four‐timepoints (2, 6, 12, and 24 hours). Results showed that H2S concentration increased, mitochondrial complex IV activity inhibited, the COX I and IV subunits and mitochondrial apoptosis pathway‐related proteins expression increased in atime‐ and dose‐dependent manner. We confirmed that 1 mg/kg NaHS had no injuryeffect on the liver, 3 and 5 mg/kg NaHS inhibitsthe activity of mitochondrial complex IV by promoting COX I and IV subunits expression, leading to the increase in ROS and ultimately inducing apoptosis and liver injury. [ABSTRACT FROM AUTHOR]
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- 2020
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33. Theanine transporters are involved in nitrogen deficiency response in tea plant (Camellia sinensis L.).
- Author
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Li, Fang, Li, Huiping, Dong, Chunxia, Yang, Tianyuan, Zhang, Shupei, Bao, Shilai, Wan, Xiaochun, and Zhang, Zhaoliang
- Published
- 2020
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34. Dexmedetomidine Protects Against Lipopolysaccharide-Induced Acute Kidney Injury by Enhancing Autophagy Through Inhibition of the PI3K/AKT/mTOR Pathway.
- Author
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Zhao, Yuan, Feng, Xiujing, Li, Bei, Sha, Jichen, Wang, Chaoran, Yang, Tianyuan, Cui, Hailin, and Fan, Honggang
- Subjects
ACUTE kidney failure ,DEXMEDETOMIDINE ,KIDNEY injuries ,BLOOD urea nitrogen ,OXIDATIVE stress ,LIPOPOLYSACCHARIDES ,ADRENERGIC receptors ,MOLECULAR pharmacology - Abstract
Background: Acute kidney injury (AKI) is often secondary to sepsis. Previous studies suggest that damaged mitochondria and the inhibition of autophagy results in AKI during sepsis, but dexmedetomidine (DEX) alleviates lipopolysaccharide (LPS)-induced AKI. However, it is uncertain whether the renoprotection of DEX is related to autophagy or the clearance of damaged mitochondria in sepsis-induced AKI. Methods: In this study, AKI was induced in rats by injecting 10 mg/kg of LPS intraperitoneally (i.p.). The rats were also pretreated with DEX (30 μg/kg, i.p.) 30 min before the injection of LPS. The structure and function of kidneys harvested from the rats were evaluated, and the protein levels of autophagy-related proteins, oxidative stress levels, and apoptosis levels were measured. Further, atipamezole (Atip) and 3-Methyladenine (3-MA), which are inhibitors of DEX and autophagy, respectively, were administered before the injection of DEX to examine the protective mechanism of DEX. Results: Pretreatment with DEX ameliorated kidney structure and function. DEX decreased the levels of blood urea nitrogen (BUN) and creatinine (Cre), urine kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), reactive oxygen species (ROS), and apoptosis proteins (such as cleaved caspase-9 and cleaved caspase-3). However, DEX upregulated the levels of autophagy and mitophagy proteins, such as Beclin-1, LC3 II and PINK1. These results suggest that DEX ameliorated LPS-induced AKI by reducing oxidative stress and apoptosis and enhancing autophagy. To promote autophagy, DEX inhibited the phosphorylation levels of PI3K, AKT, and mTOR. Furthermore, the administration of Atip and 3-MA inhibitors blocked the renoprotection effects of DEX. Conclusions: Here, we demonstrate a novel mechanism in which DEX protects against LPS-induced AKI. DEX enhances autophagy, which results in the removal of damaged mitochondria and reduces oxidative stress and apoptosis in LPS-induced AKI through the α
2 -AR and inhibition of the PI3K/AKT/mTOR pathway. [ABSTRACT FROM AUTHOR]- Published
- 2020
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35. Theanine transporters identified in tea plants (Camellia sinensis L.).
- Author
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Dong, Chunxia, Li, Fang, Yang, Tianyuan, Feng, Lin, Zhang, Shupei, Li, Fangdong, Li, Weihong, Xu, Guohua, Bao, Shilai, Wan, Xiaochun, Lucas, William J., and Zhang, Zhaoliang
- Subjects
TEA ,THEANINE ,UMAMI (Taste) ,BLOOD vessels ,AMINO acids - Abstract
Summary: Theanine, a unique non‐proteinogenic amino acid, is an important component of tea, as it confers the umami taste and relaxation effect of tea as a beverage. Theanine is primarily synthesized in tea roots and is subsequently transported to young shoots, which are harvested for tea production. Currently, the mechanism for theanine transport in the tea plant remains unknown. Here, by screening a yeast mutant library, followed by functional analyses, we identified the glutamine permease, GNP1 as a specific transporter for theanine in yeast. Although there is no GNP1 homolog in the tea plant, we assessed the theanine transport ability of nine tea plant amino acid permease (AAP) family members, with six exhibiting transport activity. We further determined that CsAAP1, CsAAP2, CsAAP4, CsAAP5, CsAAP6, and CsAAP8 exhibited moderate theanine affinities and transport was H+‐dependent. The tissue‐specific expression of these six CsAAPs in leaves, vascular tissues, and the root suggested their broad roles in theanine loading and unloading from the vascular system, and in targeting to sink tissues. Furthermore, expression of these CsAAPs was shown to be seasonally regulated, coincident with theanine transport within the tea plant. Finally, CsAAP1 expression in the root was highly correlated with root‐to‐bud transport of theanine, in seven tea plant cultivars. Taken together, these findings support the hypothesis that members of the CsAAP family transport theanine and participate in its root‐to‐shoot delivery in the tea plant. Significance Statement: In tea plants, theanine is a unique and abundant non‐proteinogenic amino acid, which confers the umami taste and relaxation effect of tea infusions. Theanine is primarily synthesized in roots and subsequently transported to young shoots which are harvested for tea production. However, the mechanism involved in this theanine transport remains unknown. In this study, members of the AAP family of amino acid transporters were identified as theanine transporters and appear to participate in theanine root‐to‐shoot transport in the tea plants. [ABSTRACT FROM AUTHOR]
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- 2020
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36. Seasonal Theanine Accumulation and Related Gene Expression in the Roots and Leaf Buds of Tea Plants (Camellia Sinensis L.).
- Author
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Li, Fang, Dong, Chunxia, Yang, Tianyuan, Ma, Jingzhen, Zhang, Shupei, Wei, Chaoling, Wan, Xiaochun, and Zhang, Zhaoliang
- Subjects
TEA ,THEANINE ,BUDS ,GENE expression ,UMAMI (Taste) ,AMINO acids - Abstract
Theanine, a unique and abundant non-proteinogenic amino acid in tea, confers to the tea infusion its umami taste and multiple health benefits. Its content in new tea shoots is dynamic in winter and spring. However, its seasonal accumulation pattern and the underlying regulation mechanism of tea plants remain largely unknown. In this study, we measured the theanine contents in the roots and leaf buds of 13 tea cultivars at four time points from winter to spring (Dec. 12, Mar. 1, Mar. 23, and Apr. 13). We found theanine accumulated significantly in the roots to as high as ∼6% dry weight. We found theanine content in the roots was constant or slightly decreased on Mar. 1 compared with Dec.12 but increased consistently on Mar. 23 and then decreased on Apr. 13 in all 13 cultivars. In the leaf buds, theanine content kept increasing from Mar. 1 to Mar. 23 and decreasing from Apr. 13 in most of the 13 cultivars, meaning it was probably both season- and developmental stage-dependent. The expression of theanine biosynthesis and amino acid transporter genes in the roots and buds at the four time points was then examined. The correlation analyses between the gene expression and theanine content suggested the expression of theanine-biosynthesis genes was generally and negatively correlated with theanine content; however, the expression of amino acid transporter genes including CsLHT was generally and positively correlated with theanine contents. Finally, we showed that CsLHT has theanine transport activity. Taken together, this study provided insight into the seasonal regulation of theanine biosynthesis and transport in tea plants during winter and spring. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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37. Integrated analysis of miRNAs and their targets reveals that miR319c/TCP2 regulates apical bud burst in tea plant (Camellia sinensis).
- Author
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Liu, Shengrui, Mi, Xiaozeng, Zhang, Ran, An, Yanlin, Zhou, Qiying, Yang, Tianyuan, Xia, Xiaobo, Guo, Rui, Wang, Xuewen, and Wei, Chaoling
- Subjects
TEA ,MICRORNA ,DORMANCY in plants ,NON-coding RNA ,BUDS ,GENE targeting ,GENE expression - Abstract
Main conclusion: The roles of microRNA-mediated epigenetic regulation were highlighted in the bud dormancy–activity cycle, implying that certain differentially expressed miRNAs play crucial roles in apical bud burst, such as csn-miR319c/TCP2. microRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression by targeting mRNA transcripts for cleavage or directing translational inhibition. To investigate whether miRNAs regulate bud dormancy–activation transition in tea plant, which largely affects the yield and price of tea products and adaptability of tea trees, we constructed small RNA libraries from three different periods of bud dormancy–burst transition. Through sequencing analysis, 262 conserved and 83 novel miRNAs were identified, including 118 differentially expressed miRNAs. Quantitative RT-PCR results for randomly selected miRNAs exhibited that our comprehensive analysis is highly reliable and accurate. The content of caffeine increased continuously from the endodormancy bud to flushing bud, and differentially expressed miRNAs coupling with their targets associated with bud burst were identified. Remarkably, csn-miR319c was downregulated significantly from the quiescent bud to burst bud, while its target gene CsnTCP2 (TEOSINTE BRANCHED/CYCLOIDEA/PROLIFERATING CELL FACTOR 2) displayed opposite expression patterns. Co-transformation experiment in tobacco demonstrated that csn-miR319c can significantly suppress the functions of CsnTCP2. This study on miRNAs and the recognition of target genes could provide new insights into the molecular mechanism of the bud dormancy–activation transition in tea plant. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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38. Dexmedetomidine ameliorates lipopolysaccharide‐induced acute kidney injury in rats by inhibiting inflammation and oxidative stress via the GSK‐3β/Nrf2 signaling pathway.
- Author
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Feng, Xiujing, Guan, Wei, Zhao, Yuan, Wang, Chaoran, Song, Manyu, Yao, Yujie, Yang, Tianyuan, and Fan, Honggang
- Subjects
KIDNEY injuries ,DEXMEDETOMIDINE ,OXIDATIVE stress ,KIDNEY tubules ,RATS ,INFLAMMATION - Abstract
Acute kidney injury (AKI) is a frequent and serious complication of sepsis; however, there are currently no effective therapies. Inflammation and oxidative stress are the major mechanisms implicated in lipopolysaccharide (LPS)‐induced AKI. Dexmedetomidine (DEX) has been reported to have remarkable anti‐inflammatory and antioxidant effects. Here, we examined the renoprotective effects of DEX and potential underlying mechanisms in rats with LPS‐induced AKI. We analyzed renal function and structure; serum inflammatory cytokine; renal oxidant and antioxidant levels; and renal expression of glycogen synthase kinase‐3β (GSK‐3β)/nuclear factor erythroid 2‐related factor 2 (Nrf2) pathway‐related proteins in rats 4 hr after administration of LPS. Pretreatment with DEX improved renal function and significantly reduced the levels of inflammatory cytokines and oxidative stress markers. Treatment with DEX and the GSK‐3β inhibitor SB216367 promoted phosphorylation of GSK‐3β, induced Nrf2 nuclear translocation, and increased transcription of the Nrf2 target genes heme oxygenase‐1 and NAD(P)H quinone oxidoreductase‐1, primarily in renal tubules. Alpha‐2‐adrenergic receptor (α2‐AR) antagonist atipamezole and imidazoline I 2 receptor (I 2R) antagonist idazoxan reversed the effects of DEX. These results suggest that the renoprotective effects of DEX are mediated via α2‐AR and I 2R‐dependent pathways that reduce inflammation and oxidative stress through GSK‐3β/Nrf2 signaling. [ABSTRACT FROM AUTHOR]
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- 2019
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39. A WRKY transcription factor PbrWRKY53 from Pyrus betulaefolia is involved in drought tolerance and AsA accumulation.
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Liu, Yue, Yang, Tianyuan, Lin, Zekun, Gu, Bingjie, Xing, Caihua, Zhao, Liangyi, Dong, Huizhen, Gao, Junzhi, Xie, Zhihua, Zhang, Shaoling, and Huang, Xiaosan
- Subjects
VITAMIN C ,DROUGHT tolerance ,FLOWERING of plants ,TRANSCRIPTION factors ,PEARS - Abstract
Summary: WRKY comprises a large family of transcription factors in plants, but most WRKY members are still poorly understood. In this study, we report the identification and functional characterization of PbrWRKY53 isolated from Pyrus betulaefolia. PbrWRKY53 was greatly up‐regulated by drought and abscisic acid, but slightly induced by salt and cold. Subcellar localization analyses showed that PbrWRKY53 was located in the nucleus. Ectopic expression of PbrWRKY53 in tobacco and Pyrus ussuriensis conferred enhanced tolerance to drought stress. The transgenic plants exhibited better water status, less reactive oxygen species generation and higher levels of antioxidant enzyme activities and metabolites than the wild type. In addition, overexpression of PbrWRKY53 in transgenic tobacco resulted in enhanced expression level of PbrNCED1, and led to the increase in larger amount of vitamin C accumulation in comparison to WT. Knock‐down of PbrWRKY53 in P. ussuriensis down‐regulated PbrNCED1 abundance, accompanied by compromised drought tolerance. Yeast one‐hybrid assay, EMSA and transient expression analysis demonstrated that PbrWRKY53 could bind to the W‐box element in the promoter region of PbrNCED1. Taken together, these results demonstrated that PbrWRKY53 plays a positive role in drought tolerance, which might be, at least in part, promoting production of vitamin C via regulating PbrNCED1 expression. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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40. Glucocorticoid-Driven NLRP3 Inflammasome Activation in Hippocampal Microglia Mediates Chronic Stress-Induced Depressive-Like Behaviors.
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Feng, Xiujing, Zhao, Yuan, Yang, Tianyuan, Song, Manyu, Wang, Chaoran, Yao, Yujie, and Fan, Honggang
- Subjects
IMMOBILIZATION stress ,NF-kappa B ,MICROGLIA - Abstract
Chronic stress is a key risk factor for depression, and microglia have been implicated in the pathogenesis of the disease. Recent studies show that the Nod-like receptor protein 3 (NLRP3) inflammasome is expressed in microglia and may play a crucial role in depression. However, the mechanism of NLRP3 inflammasome activation in hippocampal microglia and its role in depressive-like behaviors remain poorly understood. In this study, rats were subjected to 6 h of restraint stress per day for 21 days to produce a model of stress-induced depression. Behavioral tests and serum corticosterone were used to assess the success of the model. Furthermore, HAPI cells were pretreated with dexamethasone (5 × 10
–7 M) to assess stress-induced changes in microglial cells in culture. The microglial marker Iba-1, reactive oxygen species (ROS), nuclear factor kappa B (NF-κB) and key components of the NLRP3 inflammasome and its downstream inflammatory effectors (IL-1β and IL-18) were measured. Chronic stress induced depressive-like behavior, increased serum corticosterone levels and produced hippocampal structural changes. Chronic stress and dexamethasone both increased Iba-1 expression and ROS formation and also elevated levels of NF-κB, NLRP3, cleaved caspase-1, IL-1β and IL-18. After use of the NF-κB inhibitor BAY 117082 and knocked out NLRP3 in vitro decreased ROS formation and the expression of Iba-1, NF-κB and NLRP3 as well as levels of cleaved caspase-1, IL-1β and IL-18. These findings suggest that activation of the glucocorticoid receptor-NF-κB-NLRP3 pathway in hippocampal microglia mediates chronic stress-induced hippocampal neuroinflammation and depression-like behavior. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
41. Significantly increased amino acid accumulation in a novel albino branch of the tea plant (Camellia sinensis).
- Author
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Lu, Mengqian, Han, Jieyun, Zhu, Biying, Jia, Huiyan, Yang, Tianyuan, Deng, Wei-Wei, Zhang, Zheng-Zhu, and Wang, Rangjian
- Subjects
TEA ,LEUCISM ,CHLOROPHYLL ,GENE expression ,POLYPHENOLS ,THEANINE - Abstract
Main conclusion: A normal tea plant with one albino branch was discovered. RNA sequencing, albinism phenotype and ultrastructural observations provided a valuable understanding of the albino mechanism in tea plants.Tea plants with a specific color (white or yellow) have been studied extensively. A normal tea plant (Camellia sinensis cv. quntizhong) with one albino branch was discovered in a local tea plantation in Huangshan, Anhui, China. The pure albino leaves on this special branch had accumulated a fairly high content of amino acids, especially theanine (45.31 mg/g DW), and had a low concentration of polyphenols and an extremely low chlorophyll (Chl) content compared with control leaves. Ultrastructural observation of an albino leaf revealed no chloroplasts, whereas it was viable in the control leaf. RNA sequencing and differentially expressed gene (DEG) analysis were performed on the albino leaves and on control leaves from a normal green branch. The related genes involved in theanine and polyphenol biosynthesis were also investigated in this study. DEG expression patterns in Chl biosynthesis or degradation, carotenoid biosynthesis or degradation, chloroplast development, and biosynthesis were influenced in the albino leaves. Chloroplast deletion in albino leaves had probably destroyed the balance of carbon and nitrogen metabolism, leading to a high accumulation of free amino acids and a low concentration of polyphenols in the albino leaves. The obtained results can provide insight into the mechanism underlying this special albino branch phenotype, and are a valuable contribution toward understanding the albino mechanism in tea plants. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
42. Identification and characterization of cationic amino acid transporters (CATs) in tea plant ( Camellia sinensis).
- Author
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Feng, Lin, Yang, Tianyuan, Zhang, Zhaoliang, Li, Fangdong, Chen, Qi, Sun, Jun, Shi, Chengying, Deng, Weiwei, Tao, Mingmin, Tai, Yuling, Yang, Hua, Cao, Qiong, and Wan, Xiaochun
- Published
- 2018
- Full Text
- View/download PDF
43. Rice potassium transporter Os HAK1 is essential for maintaining potassium-mediated growth and functions in salt tolerance over low and high potassium concentration ranges.
- Author
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Chen, Guang, Hu, Qingdi, Luo, Le, Yang, Tianyuan, Zhang, Song, Hu, Yibing, Yu, Ling, and Xu, Guohua
- Subjects
POTASSIUM channels ,GENE expression ,SALT analysis ,PLANT translocation ,VASCULAR bundles (Plant physiology) ,ROOT growth - Abstract
Potassium ( K) absorption and translocation in plants rely upon multiple K transporters for adapting varied K supply and saline conditions. Here, we report the expression patterns and physiological roles of OsHAK1, a member belonging to the KT / KUP / HAK gene family in rice ( O ryza sativa L.). The expression of OsHAK1 is up-regulated by K deficiency or salt stress in various tissues, particularly in the root and shoot apical meristem, the epidermises and steles of root, and vascular bundles of shoot. Both oshak1 knockout mutants in comparison to their respective Dongjin or Manan wild types showed a dramatic reduction in K concentration and stunted root and shoot growth. Knockout of OsHAK1 reduced the K absorption rate of unit root surface area by ∼50-55 and ∼30%, and total K uptake by ∼80 and ∼65% at 0.05-0.1 and 1 m m K supply level, respectively. The root net high-affinity K uptake of oshak1 mutants was sensitive to salt stress but not to ammonium supply. Overexpression of OsHAK1 in rice increased K uptake and K/ Na ratio. The positive relationship between K concentration and shoot biomass in the mutants suggests that OsHAK1 plays an essential role in K-mediated rice growth and salt tolerance over low and high K concentration ranges. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
44. 3C fiber-optic quasi-distributed acoustic sensing (3C-QDAS).
- Author
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Zhang, Lixia, Jing, Qiang, Han, Bing, Rao, Yunjiang, Li, Wenhui, Xin, Peilian, Yang, Tianyuan, Gong, Yuan, Ran, Zengling, and Shao, Tianqi
- Published
- 2022
- Full Text
- View/download PDF
45. Space-based infrared staring sensor design method integrating detection and information processing technology.
- Author
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Bian, Boyuan, Chen, Ying, Zhou, Feng, Zhong, Xiaoming, Zheng, Guoxian, and Yang, Tianyuan
- Published
- 2022
- Full Text
- View/download PDF
46. A method for calculating the energy focus ability of cryogenic optical system.
- Author
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Su, Junhong, Chu, Junhao, Yu, Qifeng, Jiang, Huilin, Yang, Tianyuan, Ling, Long, Xing, Mailing, Yang, Xiaole, and Zhou, Feng
- Published
- 2021
- Full Text
- View/download PDF
47. Analysis of factors affecting of coupling efficiency of the SPIDER.
- Author
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Su, Junhong, Chu, Junhao, Yu, Qifeng, Jiang, Huilin, Yu, Gongmin, Zhang, Lei, Yin, Ke, and Yang, Tianyuan
- Published
- 2021
- Full Text
- View/download PDF
48. Removal Effect of Basic Oxygen Furnace Slag Porous Asphalt Concrete on Copper and Zinc in Road Runoff.
- Author
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Yang, Tianyuan, Chen, Meizhu, and Wu, Shaopeng
- Subjects
ASPHALT concrete ,BASIC oxygen furnaces ,LIGHTWEIGHT concrete ,COPPER slag ,ASPHALT ,POROUS metals ,HEAVY metals removal (Sewage purification) ,SLAG - Abstract
In order to improve the utilization efficiency of road runoff and the remove effects of heavy metals, porous asphalt pavements have been used as an effective measure to deal with heavy metals in road runoff. However, the removal effect on dissolved heavy metal is weak. In this paper, basic oxygen furnace (BOF) slag was used as aggregate in porous asphalt concrete to improve the removal capacity of heavy metal. Road runoff solution with a copper concentration of 0.533 mg/L and a zinc concentration of 0.865 mg/L was artificially synthesized. The removal effect of BOF slag porous asphalt concrete on cooper and zinc in runoff was evaluated by removal tests. The influence of rainfall intensity and time on the removal effect was discussed. The results obtained indicated that BOF slag porous asphalt concrete has a better removal effect on copper. The removal rate of copper is 57–79% at the rainfall intensity of 5–40 mm/h. The removal rate of zinc is more susceptible to the changes of rainfall intensity than copper. The removal rate of zinc in heavy rain conditions (40 mm/h) is only 25%. But in light rain conditions (5 mm/h), BOF slag porous asphalt concrete maintains favorable removal rates of both copper and zinc, which are more than 60%. The heavy metal content of runoff infiltrating through the BOF slag porous asphalt concrete meets the requirements for irrigation water and wastewater discharge. The results of this study provide evidence for the environmentally friendly reuse of BOF slag as a road material and the improvement of the removal of heavy metal by porous asphalt concrete. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
49. Effect of Steel Slag Aggregate on Pavement and Flame-Retardant Performance of Warm-Mixed Flame-Retardant Asphalt Concrete.
- Author
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Ren, Yanfei, Chen, Meizhu, Yang, Tianyuan, Wu, Shaopeng, Wang, Kaifeng, and Coppola, Luigi
- Subjects
ASPHALT concrete ,FIRE resistant polymers ,SLAG ,X-ray spectroscopy ,SPRAY combustion ,STEEL ,PAVEMENTS - Abstract
With the rapid development of tunnel construction, tunnel safety and the shortage of high-quality aggregates have concerned researchers so that this issue has become a research hot spot in the past few years. In the present study, we intended to prepare warm-mixed flame-retardant asphalt concrete using steel slag aggregate and evaluate its pavement and flame retardant performance. In this regard, the chemical composition and microstructure of the steel slag were studied using X-ray fluorescence analysis (XRF) and scanning electron microscopy (SEM). Then diverse pavement performances, including the dynamic stability, immersion Marshall, freeze–thaw splitting strength and low-temperature bending, were investigated for the warm-mixed flame-retardant asphalt concrete with steel slag aggregate. Moreover, a creative method of the flame spray gun combustion test was proposed to characterize the combustion degree and evaluate the flame-retardant performance of the asphalt concrete with steel slag. The experimental results show that the high-temperature and moisture stability performance are improved due to the addition of steel slag, however, the low-temperature performance is reduced for the warm-mixed flame-retardant asphalt concrete while it is still higher than the requirement value of the Chinese specification (GB/T 30596-2014). Meanwhile, the ignition temperature is increased and the ignition time is delayed for warm-mixed flame-retardant asphalt concrete because of the addition of steel slag. It is concluded that asphalt concrete with steel slag has excellent flame-retardant performance so that it is an appropriate choice for tunnel pavement. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
50. Evaluation of Thermal-Mechanical Properties of Bio-Oil Regenerated Aged Asphalt.
- Author
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Yang, Tianyuan, Chen, Meizhu, Zhou, Xinxing, and Xie, Jun
- Subjects
ASPHALT ,DYNAMIC simulation ,THERMAL expansion ,MODULUS of rigidity ,HEAT capacity - Abstract
Different proportions of bio-oil (5, 10, 15, and 20 wt%) were added into aged asphalt for its regeneration. Molecular dynamic simulations were used to measure the thermal and mechanical performances of bio-oil regenerated aged asphalt (BRAA). A new, simplified BRAA model was built to calculate the specific heat capacity, thermal expansion coefficient, elastic constant, shear modulus, bulk modulus, and Young's modulus. Simulation results showed that the thermal expansion coefficient (CTE α) of asphalt at 298 K decreased by 10% after aging. Bio-oil of 5 wt% could make the CTE α restore to the original level of base asphalt, while the addition of bio-oil would further decrease the specific heat capacity of aged asphalt. The shear modulus (G), Young's modulus (K) and bulk modulus (E) of asphalt increased after aging and decreased with the increasing amount of bio-oil. According to the calculated E/G value, the ductility of aged asphalt increased by 6.0% with the addition of 10 wt% bio-oil, while over 15 wt% bio-oil would make the ductility of BRAA decrease. In summary, the regeneration effects of bio-oil to the thermal expansion coefficient, flexibility, and ductility of aged asphalt had been proven, while excessive bio-oil would decrease the thermal stability of asphalt. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
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