471 results on '"Shi, Kun"'
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2. Inhibition of M. tuberculosis and human ATP synthase by BDQ and TBAJ-587.
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Zhang, Yuying, Lai, Yuezheng, Zhou, Shan, Ran, Ting, Zhang, Yue, Zhao, Ziqing, Feng, Ziyan, Yu, Long, Xu, Jinxu, Shi, Kun, Wang, Jianyun, Pang, Yu, Li, Liang, Chen, Hongming, Guddat, Luke W., Gao, Yan, Liu, Fengjiang, Rao, Zihe, and Gong, Hongri
- Abstract
Bedaquiline (BDQ), a first-in-class diarylquinoline anti-tuberculosis drug, and its analogue, TBAJ-587, prevent the growth and proliferation of Mycobacterium tuberculosis by inhibiting ATP synthase1,2. However, BDQ also inhibits human ATP synthase3. At present, how these compounds interact with either M. tuberculosis ATP synthase or human ATP synthase is unclear. Here we present cryogenic electron microscopy structures of M. tuberculosis ATP synthase with and without BDQ and TBAJ-587 bound, and human ATP synthase bound to BDQ. The two inhibitors interact with subunit a and the c-ring at the leading site, c-only sites and lagging site in M. tuberculosis ATP synthase, showing that BDQ and TBAJ-587 have similar modes of action. The quinolinyl and dimethylamino units of the compounds make extensive contacts with the protein. The structure of human ATP synthase in complex with BDQ reveals that the BDQ-binding site is similar to that observed for the leading site in M. tuberculosis ATP synthase, and that the quinolinyl unit also interacts extensively with the human enzyme. This study will improve researchers’ understanding of the similarities and differences between human ATP synthase and M. tuberculosis ATP synthase in terms of the mode of BDQ binding, and will allow the rational design of novel diarylquinolines as anti-tuberculosis drugs.Cryogenic electron microscopy structures of Mycobacterium tuberculosis ATP synthase and human ATP synthase bound to the anti-tuberculosis drug bedaquiline or its analogue TBAJ-587 shed light on drug binding and could lead to new treatments for tuberculosis. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Systematical Investigation on Anti-Fatigue Function and Underlying Mechanism of High Fischer Ratio Oligopeptides from Antarctic Krill on Exercise-Induced Fatigue in Mice.
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Mao, Sha-Yi, Suo, Shi-Kun, Wang, Yu-Mei, Chi, Chang-Feng, and Wang, Bin
- Abstract
High Fischer ratio oligopeptides (HFOs) have a variety of biological activities, but their mechanisms of action for anti-fatigue are less systematically studied at present. This study aimed to systematically evaluate the anti-fatigue efficacy of HFOs from Antarctic krill (HFOs-AK) and explore its mechanism of action through establishing the fatigue model of endurance swimming in mice. Therefore, according to the comparison with the endurance swimming model group, HFOs-AK were able to dose-dependently prolong the endurance swimming time, reduce the levels of the metabolites (lactic acid, blood urea nitrogen, and blood ammonia), increase the content of blood glucose, muscle glycogen, and liver glycogen, reduce lactate dehydrogenase and creatine kinase extravasation, and protect muscle tissue from damage in the endurance swimming mice. HFOs-AK were shown to enhance Na
+ -K+ -ATPase and Ca2+ -Mg2+ -ATPase activities and increase ATP content in muscle tissue. Meanwhile, HFOs-AK also showed significantly antioxidant ability by increasing the activities of superoxide dismutase and glutathione peroxidase in the liver and decreasing the level of malondialdehyde. Further studies showed that HFOs-AK could regulate the body's energy metabolism and thus exert its anti-fatigue effects by activating the AMPK signaling pathway and up-regulating the expression of p-AMPK and PGC-α proteins. Therefore, HFOs-AK can be used as an auxiliary functional dietary molecules to exert its good anti-fatigue activity and be applied to anti-fatigue functional foods. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Platinum-ruthenium-iron embedded in nitrogen-doped ordered mesoporous carbon for adrenaline electrochemical sensing study.
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Zhao, Yuxin, Zhang, Tong, Liu, Fangxun, Zheng, Man, Shi, Kun, Yang, Xin, Zhao, Pinyi, Li, Xin, Zhang, Yufan, and Wang, Huan
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METAL nanoparticles ,ADRENALINE ,DOPING agents (Chemistry) ,NITROGEN ,IRON porphyrins ,TRANSITION metals ,PLATINUM - Abstract
A novel nitrogen-doped ordered mesoporous carbon (OMC) pore-embedded growth Pt-Ru-Fe nanoparticles (Pt
1 -Ru7.5 -Fex @N-OMCs) composite was designed and synthesized for the first time. SBA-15 was used as a template, and dopamine was used as a carbon and nitrogen source and metal linking reagent. The oxidative self-polymerization reaction of dopamine was utilized to polymerize dopamine into two-dimensional ordered SBA-15 template pores. Iron porphyrin was introduced as an iron source at the same time as polymerization of dopamine, which was introduced inside and outside the pores using dopamine-metal linkage. Carbonization of polydopamine, nitrogen doping and iron nanoparticle formation were achieved by one-step calcination. Then the templates were etched to form Fex @N-OMCs, and finally the Pt1 -Ru7.5 -Fex @N-OMCs composites were stabilized by the successful introduction of platinum-ruthenium nanoparticles through the substitution reaction. The composite uniformly embeds the transition metal nanoparticles inside the OMC pores with high specific surface area, which limits the size of the metal nanoparticles inside the pores. At the same time, the metal nanoparticles are also loaded onto the surface of the OMCs, realizing the uniform loading of metal nanoparticles both inside and outside the pores. This enhances the active sites of the composite, promotes the mass transfer process inside and outside the pores, and greatly enhances the electrocatalytic performance of the catalyst. The material shows high electrocatalytic performance for adrenaline, which is characterized by a wide linear range, high sensitivity and low detection limit, and can realize the detection of actual samples. [ABSTRACT FROM AUTHOR]- Published
- 2024
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5. Altered immune pathways in patients of temporal lobe epilepsy with and without hippocampal sclerosis.
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Che, Xiang-Qian, Zhan, Shi-Kun, Song, Jiao-Jiao, Deng, Yu-Lei, Wei-Liu, Peng-Huang, Jing-Zhang, Sun, Zhan-Fang, Che, Zai-Qian, and Liu, Jun
- Abstract
Over the past decades, the immune responses have been suspected of participating in the mechanisms for epilepsy. To assess the immune related pathway in temporal lobe epilepsy (TLE), we explored the altered immune pathways in TLE patients with and without hippocampal sclerosis (HS). We analyzed RNA-seq data from 3 TLE-HS and 3 TLE-nonHS patients, including identification of differentially expressed RNA, function pathway enrichment, the protein–protein interaction network and construction of ceRNA regulatory network. We illustrated the immune related landscape of molecules and pathways on human TLE-HS. Also, we identified several differential immune related genes like HSP90AA1 and SOD1 in TLE-HS patients. Further ceRNA regulatory network analysis found SOX2-OT connected to miR-671-5p and upregulated the target gene SPP1 in TLE-HS patients. Also, we identified both SOX2-OT and SPP1 were significantly upregulated in five different databases including TLE-HS patients and animal models. Our findings established the first immune related genes and possible regulatory pathways in TLE-HS patients and animal models, which provided a novel insight into disease pathogenesis in both patients and animal models. The immune related SOX2-OT/miR-671-5p/SPP1 axis may be the potential therapeutic target for TLE-HS. [ABSTRACT FROM AUTHOR]
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- 2024
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6. The chromosome‐level assembly of the wild diploid alfalfa genome provides insights into the full landscape of genomic variations between cultivated and wild alfalfa.
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Shi, Kun, Dong, Hongbin, Du, Huilong, Li, Yuxian, Zhou, Le, Liang, Chengzhi, Şakiroğlu, Muhammet, and Wang, Zan
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ALFALFA ,GENOMES ,GENETIC overexpression ,GENE silencing ,PHENOTYPIC plasticity ,GERMPLASM ,FORAGE ,PLANT gene silencing - Abstract
Summary: Alfalfa (Medicago sativa L.) is one of the most important forage legumes in the world, including autotetraploid (M. sativa ssp. sativa) and diploid alfalfa (M. sativa ssp. caerulea, progenitor of autotetraploid alfalfa). Here, we reported a high‐quality genome of ZW0012 (diploid alfalfa, 769 Mb, contig N50 = 5.5 Mb), which was grouped into the Northern group in population structure analysis, suggesting that our genome assembly filled a major gap among the members of M. sativa complex. During polyploidization, large phenotypic differences occurred between diploids and tetraploids, and the genetic information underlying its massive phenotypic variations remains largely unexplored. Extensive structural variations (SVs) were identified between ZW0012 and XinJiangDaYe (an autotetraploid alfalfa with released genome). We identified 71 ZW0012‐specific PAV genes and 1296 XinJiangDaYe‐specific PAV genes, mainly involved in defence response, cell growth, and photosynthesis. We have verified the positive roles of MsNCR1 (a XinJiangDaYe‐specific PAV gene) in nodulation using an Agrobacterium rhizobia‐mediated transgenic method. We also demonstrated that MsSKIP23_1 and MsFBL23_1 (two XinJiangDaYe‐specific PAV genes) regulated leaf size by transient overexpression and virus‐induced gene silencing analysis. Our study provides a high‐quality reference genome of an important diploid alfalfa germplasm and a valuable resource of variation landscape between diploid and autotetraploid, which will facilitate the functional gene discovery and molecular‐based breeding for the cultivars in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Social Capital and Cross-Border Venture Capital Investments in China.
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Tan, Yi, Wang, Xiaoli, Lee, Jason Z. -H., and Shi, Kun
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VENTURE capital ,SOCIAL capital ,DECISION making in investments ,VENTURE capital companies ,SOCIAL networks - Abstract
In the context of the Chinese market, foreign cross-border venture capitalists have devised specific strategies to mitigate the challenges associated with the liabilities of foreignness, such as risks and information asymmetry. They have strategically leveraged social capital to not only decrease investment risk but also to influence their investment preferences and behaviors. To investigate the influence of different types of social capital on the investment decisions of cross-border venture capitalists, hypotheses are proposed and tested using regression analysis. Our research reveals several key findings in this regard. Firstly, cross-border venture capitalists with a robust structural social capital network exhibit a greater propensity to invest in early-stage companies. This suggests that well-established connections and partnerships within the Chinese entrepreneurial ecosystem provide a level of comfort and confidence when investing in ventures at their infancy. Interestingly, relational and cognitive social capital, though undoubtedly valuable, do not significantly impact the decision to make early-stage investments. Furthermore, we have observed that venture capitalists with higher levels of structural and cognitive social capital are more inclined to form syndications. Collaborative partnerships and shared knowledge networks seem to be crucial factors that drive syndication decisions. Lastly, venture capitalists endowed with substantial structural and relational social capital tend to allocate larger investment amounts, signifying the influence of business or personal relationships and network connections on the scale of their investments. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Leveraging Weather Dynamics in Insurance Claims Triage Using Deep Learning.
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Shi, Peng, Zhang, Wei, and Shi, Kun
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INSURANCE claims ,INSURED losses ,PROPERTY insurance ,INSURANCE companies ,WEATHER ,DEEP learning ,HAIL ,HAILSTORMS - Abstract
In property insurance claims triage, insurers often use static information to assess the severity of a claim and to identify the subsequent actions. We hypothesize that the pattern of weather conditions throughout the course of a loss event is predictive of the insured losses, and hence appropriate use of weather dynamics improves the operation of insurers' claim management. To test this hypothesis, we propose a deep learning method to incorporate dynamic weather information in the predictive modeling of the insured losses for reported claims. The proposed method features a hierarchical network architecture to address the challenges in claims triage due to the nature of weather dynamics. In the empirical analysis, we examine a portfolio of hail damage property insurance claims obtained from a major U.S. insurance carrier. When supplemented by dynamic weather information, the deep learning method exhibits substantial improvement in the hold-out predictive performance. We further design a cost-conscious decision strategy for triaging claims using the probabilistic forecasts of the insurance claim amounts. We show that leveraging weather dynamics in claims triage leads to a reduction of up to 9% and 6% in operational costs compared to when the triaging decision is based on forecasts without any weather information and with only static weather information, respectively. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. Analysis of human errors in maritime accidents: A Bayesian spatial multinomial logistic model.
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Sheng, Tianyi, Weng, Jinxian, Shi, Kun, and Han, Bing
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MARINE accidents ,HUMAN error ,TANKERS ,LIQUEFIED petroleum gas ,SHIPPING containers ,UNITIZED cargo systems ,CARGO ships - Abstract
Considering the unobserved spatial heterogeneity, this study aims to build a Bayesian spatial multinomial logistic (BSMNL) model by utilizing the geographic information from historical maritime accidents. The proposed BSMNL model can be applied to investigate the determinants of human errors involved in maritime accidents. Compared to the traditional multinomial logistic (MNL) model, the proposed BSMNL model produces a more accurate estimate of the effects of environmental and accident factors on the occurrence likelihood of human errors in maritime accidents. Results show that accidents involving cargo and container ships; tankers carrying liquefied natural gas (LNG), liquefied petroleum gas (LPG), or oil; and fishing vessels are more likely to be associated with human errors. Further, one important finding is that the involvement of fishing vessels significantly increases the occurrence probability of both negligence errors and judgment or operational errors. In addition, the occurrence likelihood of human errors is generally higher in springtime, conditions of poor visibility, the absence of strong winds or waves, and the moored or docked status. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Coverage path planning for cleaning robot based on improved simulated annealing algorithm and ant colony algorithm.
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Shi, Kun, Wu, Wendi, Wu, Zhengtian, Jiang, Baoping, and Karimi, Hamid Reza
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In the field of intelligent buildings, cleaning robots have always been a part of research. This study proposes a traversal algorithm based on the combination of simulated annealing algorithm based on monotonic heating and ant colony algorithm to solve the problem of coverage path planning during operation. Firstly, environmental modelling is conducted. Then, the principles of the two algorithms and their roles in path planning are addressed. The monotonic heating simulated annealing algorithm solves the problem of the traversal order of each part in the area, and it uses the ant colony algorithm to connect them. Simulation results show that the path coverage rate is 100% and the repetition rate is 4.85%. It can completely cover the whole area and has a low repetition rate, which greatly improves the efficiency of the cleaning robot. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Multivariate extremes in lakes.
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Woolway, R. Iestyn, Tong, Yan, Feng, Lian, Zhao, Gang, Dinh, Dieu Anh, Shi, Haoran, Zhang, Yunlin, and Shi, Kun
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LAKES ,WATER supply ,ALGAL blooms ,HEAT waves (Meteorology) ,AGRICULTURE - Abstract
Extreme within-lake conditions have the potential to exert detrimental effects on lakes. Here we use satellite observations to investigate how the occurrence of multiple types of extremes, notably algal blooms, lake heatwaves, and low lake levels, have varied in 2724 lakes since the 1980s. Our study, which focuses on bloom-affected lakes, suggests that 75% of studied lakes have experienced a concurrent increase in at least two of the extremes considered (27% defined as having a notable increase), with 25% experiencing an increase in frequency of all three extremes (5% had a notable increase). The greatest increases in the frequency of these extremes were found in regions that have experienced increases in agricultural fertilizer use, lake warming, and a decline in water availability. As extremes in lakes become more common, understanding their impacts must be a primary focus of future studies and they must be carefully considered in future risk assessments. Satellite data reveals a rise in multivariate extreme events in lakes since the 1980s, largely linked to agricultural practices and mean climatic warming. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Developing and validating a nomogram for early predicting the need for intestinal resection in pediatric intussusception.
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Yuan-Yang Yu, Jia-Jie Zhang, Ya-Ting Xu, Zheng-Xiu Lin, Shi-Kun Guo, Zhong-Rong Li, Hui-Ya Huang, and Xiao-Zhong Huang
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- 2024
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13. Preclinical efficacy of CBR-5884 against epithelial ovarian cancer cells by targeting the serine synthesis pathway.
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Gong, Kunxiang, Huang, Yinger, Zheng, Yanqin, Zhu, Yinfu, Hao, Wenbo, and Shi, Kun
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OVARIAN epithelial cancer ,SERINE ,CANCER cells ,TRANSFORMING growth factors ,RNA sequencing ,TUMOR growth - Abstract
Reprogramming of the serine synthesis pathway (SSP) is intricately linked to the progression of epithelial ovarian cancer (EOC). CBR-5884, a selective small-molecule inhibitor targeting phosphoglycerate dehydrogenase (PHGDH), effectively impedes the de novo synthesis of serine within cancer cells. This study aimed to evaluate the inhibitory effect of CBR-5884 on EOC cells and delineate its specific mechanism, thereby proposing a novel therapeutic approach for treating EOC. The suppression of serine biosynthesis after CBR-5884 treatment was evaluated using RNA sequencing and a serine assay kit, and the results showed that CBR-5884 effectively downregulated serine biosynthesis in EOC cells, particularly those expressing high levels of PHGDH. In vitro studies revealed that CBR-5884 demonstrated significant antitumor effects and suppressed migration and invasion of EOC cells through down-regulation of the integrin subunit beta 4 (ITGB4)/extracellular signal-regulated kinase (ERK)/epithelial–mesenchymal transition signal axis. Additionally, CBR-5884 mitigated the stemness of EOC cells and heightened their sensitivity to chemotherapy. Moreover, in vivo studies revealed that CBR-5884 significantly delayed tumor growth, with histological analysis indicating the safety profile of CBR-5884. Finally, the patient-derived organoid (PDO) models were utilized to explore the preclinical efficacy of CBR-5884 against EOC cells, and the results unveiled that CBR-5884 impeded proliferation and downregulated the expression of ITGB4 in EOC PDO models. Our findings supports the anticancer properties of CBR-5884 in EOC cells exhibiting high PHGDH expression, manifesting through the suppression of proliferation, migration, and invasion, while enhancing chemotherapy sensitivity, suggesting that CBR-5884 holds promise as an efficacious strategy for the treatment of EOC. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Mitochondrial antioxidant elamipretide improves learning and memory impairment induced by chronic sleep deprivation in mice.
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Zhang, Yue‐Ming, Wang, Ya‐Tao, Wei, Ru‐Meng, Li, Xue‐Yan, Luo, Bao‐Ling, Zhang, Jing‐Ya, Zhang, Kai‐Xuan, Fang, Shi‐Kun, Liu, Xue‐Chun, and Chen, Gui‐Hai
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- 2024
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15. Access to Tetrahydrothiopyrano[2,3‐b]Indole Derivatives via Zinc‐Catalyzed Asymmetric [3+3] Annulation of Indoline‐2‐Thiones with Yne–Enones.
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Cui, Dan‐Dan, Shi, Jian‐Wen, Wang, Tong, Hua, Yuan‐Zhao, Wang, Min‐Can, Mei, Guang‐Jian, Niu, Jun‐Long, and Jia, Shi‐Kun
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ANNULATION ,INDOLE derivatives ,ZINC catalysts ,LEWIS acids ,DOUBLE bonds ,LEWIS bases ,DERIVATIZATION - Abstract
We report herein an enantioselective [3+3] annulation of indoline‐2‐thiones with yne–enones by chiral dinuclear zinc catalysts via a Brønsted base and Lewis acid cooperative activation model. This transformation proceeded through sequential conjugate addition, allenyl ketone formation and intramolecular sulfa‐Michael 6‐endo‐trig cyclization. A range of enantioenriched tetrahydrothiopyrano[2,3‐b]indole derivatives bearing an exocyclic double bond were obtained in moderate yields with excellent stereoselectivities (up to 20 : 1 dr, 20:1 Z/E ratio and 95% ee). Late‐stage functionalization, large‐scale experiment and further derivatizations were also explored. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. Substrate Directed Regio‐ and Enantioselective Ring‐Opening of Epoxides and Aziridines.
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Sun, Wen‐Na, Mei, Guang‐Jian, and Jia, Shi‐Kun
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EPOXY compounds ,BIOACTIVE compounds ,AZIRIDINES ,ETHYLENE oxide ,AMINO alcohols - Abstract
The oxirane and aziridine rings are valuable building blocks in modern synthetic chemistry and catalytic asymmetric ring opening reactions of these three membered ring systems have emerged as a powerful chemical tool for the synthesis of natural products and biologically active compounds. In this context, the regioselective ring‐opening of structurally or electronically unbiased epoxides and aziridines is challenging. Recently, metal‐catalyzed substrate directed strategies have successfully applied in the regio‐ and enantioselective ring opening of functionalized epoxy alcohols by the Yamamoto group. Subsequently, our group realized the ring opening reactions of functionalized 2,3‐aziridinyl alcohols with the dinuclear zinc complex. These enantioselective nucleophilic ring opening reactions of functionalized epoxy alcohols and aziridinyl alcohols allow for the facile synthesis of amino alcohol derivatives and the introduction of new concepts in catalysis. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Worldwide Swine Tuberculosis-Positive Rate and Associated Risk Factors, 1966–2020: A Systematic Review and Meta-Analysis.
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Zheng, Wei, Diao, Nai-Chao, Wang, Qi, Wang, Chun-Yu, Su, Nuo, Yin, Ji-Ying, Tian, Tian, Shi, Kun, and Du, Rui
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MYCOBACTERIUM tuberculosis ,ANIMAL herds ,ZOONOSES ,SWINE breeds ,ANIMAL culture ,MYCOBACTERIUM bovis ,SWINE - Abstract
Background: Tuberculosis (TB) is a chronic, zoonotic infectious disease caused by Mycobacterium tuberculosis that infects not only humans but also animals such as pigs, cows, buffaloes, sheep, and goats. Among them, pigs are one of the main food animals in the world. If pigs are infected with M. tuberculosis, meat products will be negatively affected, causing economic losses to the livestock industry. There is currently no systematic epidemiological assessment of swine TB in the world, so it is important to know the prevalence of swine, and these data are currently lacking, so we performed a statistical analysis. Results: We searched 6791 articles and finally included data from 35,303 pigs from 15 countries or territories, showing a combined prevalence of TB in pigs of 12.1% (95% confidence interval [CI]: 9.2 to 15.9). Among them, the prevalence rate of swine TB in Europe was 15.2% (95% CI: 11.1 to 20.7, 2491/25,050), which was higher compared with other continents, and the difference was significant; the positive rate of PCR method was higher in the detection method subgroup, which was 15.7% (95% CI: 8.0 to 31.0, 376/2261); Mycobacterium bovis was detected in pigs in the M. tuberculosis typing group (9.5%, 95% CI: 6.7 to 13.5, 1364/21,430). The positive rate is higher compared with Mycobacterium capris. Conclusion: This systematic review and meta-analysis is the first to determine the global prevalence of TB in swine herds. Although the seroprevalence of swine TB in this article is very low, the harm of TB cannot be ignored. It is important to take effective control and preventive measures to stop the spread of TB to reduce the impact of diseased pigs on animal husbandry and human health. [ABSTRACT FROM AUTHOR]
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- 2024
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18. An alfalfa MYB‐like transcriptional factor MsMYBH positively regulates alfalfa seedling drought resistance and undergoes MsWAV3‐mediated degradation.
- Author
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Shi, Kun, Liu, Jia, Liang, Huan, Dong, Hongbin, Zhang, Jinli, Wei, Yuanhong, Zhou, Le, Wang, Shaopeng, Zhu, Jiahao, Cao, Mingshu, Jones, Chris S., Ma, Dongmei, and Wang, Zan
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ALFALFA ,DROUGHTS ,GENOME-wide association studies ,TANDEM repeats ,SEEDLINGS - Abstract
Drought is a major threat to alfalfa (Medicago sativa L.) production. The discovery of important alfalfa genes regulating drought response will facilitate breeding for drought‐resistant alfalfa cultivars. Here, we report a genome‐wide association study of drought resistance in alfalfa. We identified and functionally characterized an MYB‐like transcription factor gene (MsMYBH), which increases the drought resistance in alfalfa. Compared with the wild‐types, the biomass and forage quality were enhanced in MsMYBH overexpressed plants. Combined RNA‐seq, proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1, MsMCP2, MsPRX1A and MsCARCAB to improve their expression. The outcomes of such interactions include better water balance, high photosynthetic efficiency and scavenge excess H2O2 in response to drought. Furthermore, an E3 ubiquitin ligase (MsWAV3) was found to induce MsMYBH degradation under long‐term drought, via the 26S proteasome pathway. Furthermore, variable‐number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms, and the variation is associated with promoter activity. Collectively, our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought‐resistant alfalfa. This discovery also offers new insights into the mechanisms of drought resistance in alfalfa. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Deep Learning-Based Cause-Related Marketing and the Impact of the Internet on MICE Events in the Context of the Epidemic.
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Shi, Kun, Cui, Boshi, Zhao, XinTong, Ma, Yuwei, Yang, Yang, and Du, Zewen
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SOCIAL marketing ,ARTIFICIAL neural networks ,DEEP learning ,INTERNET marketing ,CONSUMER attitudes ,MICE ,BIOLOGICAL neural networks - Abstract
Since 2019, novel coronavirus pneumonia has been rampant around the world, and when outbreaks occur, Meetings, Incentives, Conferences and Exhibitions (MICE) events are often affected to varying degrees. In addition, in the context of the epidemic, consumers have increasingly taken the participation of MICE in charitable activities as a measure of their social responsibility and judged MICE events as good or bad accordingly. Therefore, the impact of deep learning-based good cause marketing and the Internet on MICE events in the context of the epidemic has attracted much attention. Based on the CiteSpace analysis, this study systematically reviewed the impact system of cause-related marketing on exhibition activities and fitted the neural network model with a single-factor inter-group experiment. The results show that when the complete data set is divided into 70% training set and 30% test set, the model with the training function of Train lm and seven hidden layers performs best in all models. This shows that in the process of charity marketing, the fit between consumers and charity activities determines the attitude and willingness of consumers to participate in charity marketing. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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20. Development of a Thermodynamically Favorable Multi‐enzyme Cascade Reaction for Efficient Sustainable Production of ω‐Amino Fatty Acids and α,ω‐Diamines.
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Li, Ju‐Mou, Shi, Kun, Li, Ai‐Tao, Zhang, Zhi‐Jun, Yu, Hui‐Lei, and Xu, Jian‐He
- Abstract
Aliphatic ω‐amino fatty acids (ω‐AFAs) and α,ω‐diamines (α,ω‐DMs) are essential monomers for the production of nylons. Development of a sustainable biosynthesis route for ω‐AFAs and α,ω‐DMs is crucial in addressing the challenges posed by climate change. Herein, we constructed an unprecedented thermodynamically favorable multi‐enzyme cascade (TherFavMEC) for the efficient sustainable biosynthesis of ω‐AFAs and α,ω‐DMs from cheap α,ω‐dicarboxylic acids (α,ω‐DAs). This TherFavMEC was developed by incorporating bioretrosynthesis analysis tools, reaction Gibbs free energy calculations, thermodynamic equilibrium shift strategies and cofactor (NADPH&ATP) regeneration systems. The molar yield of 6‐aminohexanoic acid (6‐ACA) from adipic acid (AA) was 92.3 %, while the molar yield from 6‐ACA to 1,6‐hexanediamine (1,6‐HMD) was 96.1 %, which were significantly higher than those of previously reported routes. Furthermore, the biosynthesis of ω‐AFAs and α,ω‐DMs from 20.0 mM α,ω‐DAs (C6‐C9) was also performed, giving 11.2 mM 1,6‐HMD (56.0 % yield), 14.8 mM 1,7‐heptanediamine (74.0 % yield), 17.4 mM 1,8‐octanediamine (87.0 % yield), and 19.7 mM 1,9‐nonanediamine (98.5 % yield), respectively. The titers of 1,9‐nonanediamine, 1,8‐octanediamine, 1,7‐heptanediamine and 1,6‐HMD were improved by 328‐fold, 1740‐fold, 87‐fold and 3.8‐fold compared to previous work. Therefore, this work holds great potential for the bioproduction of ω‐AFAs and α,ω‐DMs. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Targeting vulnerable microcircuits in the ventral hippocampus of male transgenic mice to rescue Alzheimer-like social memory loss.
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Lei, Hui-Yang, Pi, Gui-Lin, He, Ting, Xiong, Rui, Lv, Jing-Ru, Liu, Jia-Le, Wu, Dong-Qin, Li, Meng-Zhu, Shi, Kun, Li, Shi-Hong, Yu, Na-Na, Gao, Yang, Yu, Hui-Ling, Wei, Lin-Yu, Wang, Xin, Zhou, Qiu-Zhi, Zou, Pei-Lin, Zhou, Jia-Yang, Liu, Ying-Zhou, and Shen, Nai-Ting
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COLLECTIVE memory ,MEMORY loss ,EPISODIC memory ,TRANSGENIC mice ,ALZHEIMER'S disease ,HIPPOCAMPUS (Brain) - Abstract
Background: Episodic memory loss is a prominent clinical manifestation of Alzheimer's disease (AD), which is closely related to tau pathology and hippocampal impairment. Due to the heterogeneity of brain neurons, the specific roles of different brain neurons in terms of their sensitivity to tau accumulation and their contribution to AD-like social memory loss remain unclear. Therefore, further investigation is necessary. Methods: We investigated the effects of AD-like tau pathology by Tandem mass tag proteomic and phosphoproteomic analysis, social behavioural tests, hippocampal electrophysiology, immunofluorescence staining and in vivo optical fibre recording of GCaMP6f and iGABASnFR. Additionally, we utilized optogenetics and administered ursolic acid (UA) via oral gavage to examine the effects of these agents on social memory in mice. Results: The results of proteomic and phosphoproteomic analyses revealed the characteristics of ventral hippocampal CA1 (vCA1) under both physiological conditions and AD-like tau pathology. As tau progressively accumulated, vCA1, especially its excitatory and parvalbumin (PV) neurons, were fully filled with mislocated and phosphorylated tau (p-Tau). This finding was not observed for dorsal hippocampal CA1 (dCA1). The overexpression of human tau (hTau) in excitatory and PV neurons mimicked AD-like tau accumulation, significantly inhibited neuronal excitability and suppressed distinct discrimination-associated firings of these neurons within vCA1. Photoactivating excitatory and PV neurons in vCA1 at specific rhythms and time windows efficiently ameliorated tau-impaired social memory. Notably, 1 month of UA administration efficiently decreased tau accumulation via autophagy in a transcription factor EB (TFEB)-dependent manner and restored the vCA1 microcircuit to ameliorate tau-impaired social memory. Conclusion: This study elucidated distinct protein and phosphoprotein networks between dCA1 and vCA1 and highlighted the susceptibility of the vCA1 microcircuit to AD-like tau accumulation. Notably, our novel findings regarding the efficacy of UA in reducing tau load and targeting the vCA1 microcircuit may provide a promising strategy for treating AD in the future. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Targeting vulnerable microcircuits in the ventral hippocampus of male transgenic mice to rescue Alzheimer-like social memory loss.
- Author
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Lei, Hui-Yang, Pi, Gui-Lin, He, Ting, Xiong, Rui, Lv, Jing-Ru, Liu, Jia-Le, Wu, Dong-Qin, Li, Meng-Zhu, Shi, Kun, Li, Shi-Hong, Yu, Na-Na, Gao, Yang, Yu, Hui-Ling, Wei, Lin-Yu, Wang, Xin, Zhou, Qiu-Zhi, Zou, Pei-Lin, Zhou, Jia-Yang, Liu, Ying-Zhou, and Shen, Nai-Ting
- Subjects
COLLECTIVE memory ,MEMORY loss ,EPISODIC memory ,TRANSGENIC mice ,ALZHEIMER'S disease ,HIPPOCAMPUS (Brain) - Abstract
Background: Episodic memory loss is a prominent clinical manifestation of Alzheimer's disease (AD), which is closely related to tau pathology and hippocampal impairment. Due to the heterogeneity of brain neurons, the specific roles of different brain neurons in terms of their sensitivity to tau accumulation and their contribution to AD-like social memory loss remain unclear. Therefore, further investigation is necessary. Methods: We investigated the effects of AD-like tau pathology by Tandem mass tag proteomic and phosphoproteomic analysis, social behavioural tests, hippocampal electrophysiology, immunofluorescence staining and in vivo optical fibre recording of GCaMP6f and iGABASnFR. Additionally, we utilized optogenetics and administered ursolic acid (UA) via oral gavage to examine the effects of these agents on social memory in mice. Results: The results of proteomic and phosphoproteomic analyses revealed the characteristics of ventral hippocampal CA1 (vCA1) under both physiological conditions and AD-like tau pathology. As tau progressively accumulated, vCA1, especially its excitatory and parvalbumin (PV) neurons, were fully filled with mislocated and phosphorylated tau (p-Tau). This finding was not observed for dorsal hippocampal CA1 (dCA1). The overexpression of human tau (hTau) in excitatory and PV neurons mimicked AD-like tau accumulation, significantly inhibited neuronal excitability and suppressed distinct discrimination-associated firings of these neurons within vCA1. Photoactivating excitatory and PV neurons in vCA1 at specific rhythms and time windows efficiently ameliorated tau-impaired social memory. Notably, 1 month of UA administration efficiently decreased tau accumulation via autophagy in a transcription factor EB (TFEB)-dependent manner and restored the vCA1 microcircuit to ameliorate tau-impaired social memory. Conclusion: This study elucidated distinct protein and phosphoprotein networks between dCA1 and vCA1 and highlighted the susceptibility of the vCA1 microcircuit to AD-like tau accumulation. Notably, our novel findings regarding the efficacy of UA in reducing tau load and targeting the vCA1 microcircuit may provide a promising strategy for treating AD in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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23. LSD1 in drug discovery: From biological function to clinical application.
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Liu, Hui‐Min, Zhou, Ying, Chen, He‐Xiang, Wu, Jiang‐Wan, Ji, Shi‐Kun, Shen, Liang, Wang, Shao‐Peng, Liu, Hong‐Min, Liu, Ying, Dai, Xing‐Jie, and Zheng, Yi‐Chao
- Subjects
DRUG discovery ,FLAVIN adenine dinucleotide ,CLINICAL medicine ,MONOAMINE oxidase ,GENE silencing ,GENE targeting - Abstract
Lysine‐specific demethylase 1 (LSD1) is a flavin adenine dinucleotide (FAD) dependent monoamine oxidase (MAO) that erases the mono‐, and dimethylation of histone 3 lysine 4 (H3K4), resulting in the suppression of target gene transcriptions. Besides, it can also demethylate some nonhistone substrates to regulate their biological functions. As reported, LSD1 is widely upregulated and plays a key role in several kinds of cancers, pharmacological or genetic ablation of LSD1 in cancer cells suppresses cell aggressiveness by several distinct mechanisms. Therefore, numerous LSD1 inhibitors, including covalent and noncovalent, have been developed and several of them have entered clinical trials. Herein, we systemically reviewed and discussed the biological function of LSD1 in tumors, lymphocytes as well as LSD1‐targeting inhibitors in clinical trials, hoping to benefit the field of LSD1 and its inhibitors. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Uterine Commensal Peptostreptococcus Species Contribute to IDO1 Induction in Endometrial Cancer via Indoleacrylic Acid.
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Wang, Qiong, Liu, Yaqiong, Chen, Weiwei, Chen, Sha, Su, Minting, Zheng, Yanqin, Liu, Wenjie, Li, Li, Zeng, Liang, Shi, Quan, He, Juan, Qian, Yuanmin, Xuan, Xingcui, Wen, Qirong, Lash, Gendie E., and Shi, Kun
- Subjects
INDOLEACETIC acid ,ENDOMETRIAL cancer ,MONONUCLEAR leukocytes ,GENITALIA - Abstract
Microbial dysbiosis has an increasingly appreciated impact on carcinogenesis, and the cervicovaginal microbiome plays a critical role in microenvironmental inflammation. Here, we investigated the involvement of the female genital tract Peptostreptococcus species in gynecological cancer via indoleacrylic acid (IAA). IAA production from Peptostreptococcus species and the effect of bacterial culture on tumor growth in vivo were examined. The impact of IAA on cytokine production and indoleamine-2,3-dioxygenase 1 (IDO1) expression in an endometrial cancer (EC) cell line, as well as their effect on T
reg and Teff cells, and M1 and M2 macrophage populations were examined in EC patients and tumor-grafted mice. Clinically, Peptostreptococcus species abundance, IAA, and IDO1 expression were verified in EC patients. The results showed that IAA production was induced in the uteri of BALB/c nude mice by Peptostreptococcus species transplantation, and the intratumoral injection of a conditioned medium from Peptostreptococcus cultures into tumor-grafted mice promoted tumor growth. IL-10 expression was upregulated by IAA; IFN-γ expression was increased by IL-10. IFN-γ induced IDO1 expression in the EC cell line. The co-culture of IDO1-expressing EC cells with peripheral blood mononuclear cells upregulated the Treg proportion and decreased the M1/M2 ratio. Clinically, P. anaerobius was more abundant amongst the uterine microbiota of EC patients than the control. The IAA, IDO1, and kynurenine/tryptophan ratios were all higher in EC tissue, and the M1/M2 ratio was lower. Our study sheds light on the link between IDO1 induction and uterine Peptostreptococcus dysbiosis and provides a potential rationale for the role of Peptostreptococcus species in immune tolerance induction in type I endometrial cancer. [ABSTRACT FROM AUTHOR]- Published
- 2024
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25. On the Solute Concentration and Corrosion Susceptibility of Mg-xMn-4.0Gd Alloy.
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Gu, Dong-dong, Wu, Wen-xing, Xie, Shi-kun, and Peng, Jian
- Abstract
In this paper, the Fe/Si reduction efficiency, Gd/Mn alloying efficiency, and corrosion susceptibility of the Mg-xMn-4.0Gd alloy were investigated. The results reveal that adding Mn gives a more prominent Fe removal effect under the conventional smelting processes. Neither the amount of Gd addition nor excessive Mn addition is sufficient for the continued strengthening of the Fe removal effect. The alloying efficiency of Mn increased and then decreased as a result of adding Mn alone to mixtures of Mn and Gd elements, while the alloying efficiency of Gd elements gradually diminished. An appropriate amount of Mn addition is beneficial for efficiently improving the corrosion resistance of the alloy. The extruded Mg-0.8Mn-4.0Gd alloy has more outstanding corrosion resistance, with a CR
Weighet Loss of 4.48 ± 0.33 mg/(cm2 ·d) and CRHydrogen Evolution of 2.01 ± 0.31 ml/(cm2 ·d). The corrosion susceptibility of the extruded Mg-xMn-4.0Gd alloy mainly hinges on the grain size, Gd solid solubility, and texture intensity of basal plane I(0002) . [ABSTRACT FROM AUTHOR]- Published
- 2024
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26. A Smart Stimulation–Deadhesion and Antimicrobial Hydrogel for Repairing Diabetic Wounds Infected with Methicillin‐Resistant Staphylococcus aureus.
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Bei, Zhongwu, Zhang, Linghong, Li, Jianan, Tong, Qi, Shi, Kun, Chen, Wen, Yu, Yan, Sun, Ao, Xu, Yang, Liu, Jie, and Qian, Zhiyong
- Published
- 2024
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27. ZSWIM4 inhibition improves chemosensitivity in epithelial ovarian cancer cells by suppressing intracellular glycine biosynthesis.
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Gong, Kunxiang, Huang, Yinger, Zheng, Yanqin, Hao, Wenbo, and Shi, Kun
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OVARIAN epithelial cancer ,DRUG resistance in cancer cells ,CANCER cells ,BIOSYNTHESIS ,SURFACE plasmon resonance - Abstract
Background: Zinc finger SWIM-type containing 4 (ZSWIM4) induces drug resistance in breast cancer cells. However, its role in epithelial ovarian cancer (EOC) remains unknown. In this study, we aimed to investigate the clinical significance of ZSWIM4 expression in EOC and develop new clinical therapeutic strategies for EOC. Methods: ZSWIM4 expression in control and EOC tumor tissues was examined using immunohistochemistry. Lentiviral transduction, Cell Counting Kit-8 assay, tumorsphere formation assay, flow cytometry, western blotting, and animal xenograft model were used to assess the role of ZSWIM4 in chemotherapy. Cleavage Under Targets and Tagmentation (CUT&Tag) assays, chromatin immunoprecipitation assays, and luciferase reporter assays were used to confirm FOXK1-mediated upregulation of ZSWIM4 expression. The mechanism by which ZSWIM4 inhibition improves chemosensitivity was evaluated using RNA-sequencing. A ZSWIM4-targeting inhibitor was explored by virtual screening and surface plasmon resonance analysis. Patient-derived organoid (PDO) models were constructed from EOC tumor tissues with ZSWIM4 expression. Results: ZSWIM4 was overexpressed in EOC tumor tissues and impaired patient prognoses. Its expression correlated positively with EOC recurrence. ZSWIM4 expression was upregulated following carboplatin treatment, which, in turn, contributed to chemoresistance. Silencing ZSWIM4 expression sensitized EOC cells to carboplatin treatment in vitro and in vivo. FOXK1 could bind to the GTAAACA sequence of the ZSWIM4 promoter region to upregulate ZSWIM4 transcriptional activity and FOXK1 expression increased following carboplatin treatment, leading to an increase in ZSWIM4 expression. Mechanistically, ZSWIM4 knockdown downregulated the expression of several rate-limiting enzymes involved in glycine synthesis, causing a decrease in intracellular glycine levels, thus enhancing intracellular reactive oxygen species production induced by carboplatin treatment. Compound IPN60090 directly bound to ZSWIM4 protein and exerted a significant chemosensitizing effect in both EOC cells and PDO models. Conclusions: ZSWIM4 inhibition enhanced EOC cell chemosensitivity by ameliorating intracellular glycine metabolism reprogramming, thus providing a new potential therapeutic strategy for EOC. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Degraders in epigenetic therapy: PROTACs and beyond.
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Xing-Jie Dai, Shi-Kun Ji, Meng-Jie Fu, Gao-Zhi Liu, Hui-Min Liu, Shao-Peng Wang, Liang Shen, Ning Wang, Herdewijn, Piet, Yi-Chao Zheng, Sai-Qi Wang, and Xiao-Bing Chen
- Published
- 2024
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29. Formation and effect of rough surface in pulsed laser removal of thick paint layer on 2024 aluminum.
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Zhu, Ming, Zhang, Hao, Shi, Kun, Hou, Xiaofei, Shi, Yu, Fan, Ding, and Zhang, Wenzhu
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ROUGH surfaces ,THERMAL stresses ,SURFACE roughness ,ALUMINUM alloys ,ALUMINUM ,PULSED lasers - Abstract
When using pulsed laser to remove a thick paint layer from a 2024 aluminum alloy substrate, the paint layer should be removed layer by layer, and the substrate should remain intact after the paint layer is completely removed. In this process, the formation of a rough surface on the paint increases laser absorption, changing the removal mechanism, which becomes an unstable factor for nondestructive paint removal. This study investigated the laser paint removal mechanism of fluorocarbon paint and found that when the laser fluence was 0.91 J/cm
2 , the main removal mechanisms were thermal stress and combustion-decomposition removal, while at 94.36 J/cm2 , the main mechanism was sputtering removal. The study also investigated the relationship between surface roughness and the number of laser scans, which showed a positive linear correlation. Additionally, an equivalent model of a rough surface was established to analyze the changes in absorption, though this model has yet to be verified and further research and validation is required to confirm our findings. [ABSTRACT FROM AUTHOR]- Published
- 2024
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30. Construction and assessment of an indicator system of stream conditions in a typical mountain landscape in Northeast China.
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Dong, Baili, Zhou, Yongqiang, Peng, Kai, Qin, Boqiang, and Shi, Kun
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ENVIRONMENTAL health ,ECOSYSTEM management ,ANTHROPOGENIC effects on nature ,ECOLOGICAL assessment ,ECOSYSTEM health ,DEFORESTATION - Abstract
Stream ecosystem health assessments are crucial for the effective management of aquatic ecosystem service functions and the assessment of anthropogenic and climatic impacts on aquatic ecosystems. However, there is still a lack of comprehensive assessment methods based on complete ecosystem structures. This study improved an ecological health assessment system, which consists of 13 indicators based on ecosystem structure. The assessment system was applied to 30 streams on Changbai Mountain. The results showed that the comprehensive index of stream health (ISH) in Changbai Mountain was relatively high, and the ISH increased with the elevation gradient. The dominant factors controlling the ecosystem health level were water pH, water flow, vegetation coverage, total phosphorus (TP), and vegetation diversity index. All these results indicated that the damage caused by excessive deforestation and farmland occupation in recent years has not been fully reversed and that human disturbance from tourism may be the main reason for the low stream health at lower elevations. Our results suggest that the key to future work is to increase quantitative research on disturbance sensitivity and to develop economically viable restoration measures. [ABSTRACT FROM AUTHOR]
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- 2024
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31. Adsorption removal of fluoride from polluted drinking waters using Mn-Al-La oxide.
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Deng, Yilei, Wang, Shuyue, Shi, Kun, and Xiong, Huixin
- Subjects
GROUNDWATER purification ,DRINKING water ,ADSORPTION (Chemistry) ,WATER use ,ADSORPTION capacity ,ELECTROSTATIC interaction ,FLUORIDES - Abstract
Trimetal oxides have received high attention in treatment of fluoride-polluted drinking waters. In this study, Mn-Al-La (MAL) oxide with a mole ratio of 2:1:1 was successively prepared and characterized by XRD, FTIR, XPS, and TEM. It exhibited as cotton-like assemblages (500–800 nm of axial lengths), and BET specific surface area was 52 m
2 /g. It was used to study fluoride adsorptions in aqueous solutions by batch experiments, under different adsorbent/adsorbate levels, times, temperatures, pH and coexisting anions, and treat simulated groundwater (with 2.85 mg/L fluoride and pH 7.0) by batch and column tests. Adsorption data well fitted to pseudo-second-order rate model (R2 = 0.996–0.999), and Langmuir (R2 = 0.962 − 0.997) and Freundlich (R2 = 0.964–0.989) isothermal models. Their maximum adsorption capacities could reach 45–113 mg/g. Only H2 PO4 − anions had a restrictive impact at pH 7.0, and there was a good removal ability at pH 3–9. Adsorption processes were spontaneous, endothermic, and random. Adsorption mechanisms were electrostatic interaction and ligand exchange at pH 7.0. Adsorption capacity could reach 73% of initial value at pH 7.0, after three cycles. All application data on the polluted groundwater treatments show MAL oxide is a potential adsorbent for fluoride removals. [ABSTRACT FROM AUTHOR]- Published
- 2024
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32. The impact of extreme heat on lake warming in China.
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Wang, Weijia, Shi, Kun, Wang, Xiwen, Zhang, Yunlin, Qin, Boqiang, Zhang, Yibo, and Woolway, R. Iestyn
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WATER temperature ,SURFACE temperature ,GLOBAL warming ,SURFACE dynamics ,HEAT waves (Meteorology) - Abstract
Global lake ecosystems are subjected to an increased occurrence of heat extremes, yet their impact on lake warming remains poorly understood. In this study, we employed a hybrid physically-based/statistical model to assess the contribution of heat extremes to variations in surface water temperature of 2260 lakes in China from 1985 to 2022. Our study indicates that heat extremes are increasing at a rate of about 2.08 days/decade and an intensity of about 0.03 °C/ day·decade in China. The warming rate of lake surface water temperature decreases from 0.16 °C/decade to 0.13 °C/decade after removing heat extremes. Heat extremes exert a considerable influence on long-term lake surface temperature changes, contributing 36.5% of the warming trends within the studied lakes. Given the important influence of heat extremes on the mean warming of lake surface waters, it is imperative that they are adequately accounted for in climate impact studies. Heat extremes occur more frequently with global warming. Here the authors show that short-term heat extremes play a critical role in shaping long-term dynamics of lake surface temperature, contributing 36.5% of the warming trends in Chinese lakes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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33. Internal revenue sharing methodology for virtual power plant clusters considering carbon incentive and penalty mechanisms.
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Gong, Taorong, Chen, Songsong, Shi, Kun, Chai, Zhichao, and Wang, Yu
- Subjects
INTERNAL revenue ,FULLERENES ,INCENTIVE (Psychology) ,CLEAN energy ,SUSTAINABILITY ,POWER plants ,COAL-fired power plants - Abstract
With the rapid development of renewable energy and the urgent need for global carbon emission reduction, virtual power plants have become a high-profile energy management model that can integrate multiple energy resources. How to effectively integrate renewable energy to reduce carbon emissions, how to optimize the use of different energy resources, and how to fairly distribute economic benefits within virtual power plant clusters while encouraging the reduction of carbon emissions are issues that need to be addressed in research. The study first established a virtual power plant model and conducted in-depth optimization for its economic and environmental indicators. Subsequently, the study constructed a game model within the virtual power plant cluster, aiming to solve the problem of income distribution in this diversified energy system. The research results found that commercial users have the highest carbon emissions, followed by industrial users, while residential users have the lowest carbon emissions. In terms of optimized user electricity consumption behavior, the peak-to-valley difference rate of industrial users has been reduced by 17%, and the daily load rate has increased by 6%; the peak-to-valley difference rate of commercial users has been reduced by 12%, and the daily load rate has increased by 6%; The peak-to-trough difference rate for residential users decreased by 8%, and the daily load rate increased by 4%. In addition, the research also proposes a method of internal revenue distribution of virtual power plant clusters based on a carbon reward and punishment mechanism, which provides a new way for the synergy effects and economic benefit distribution of virtual power plants. Research is of positive significance in solving pressing issues in the field of energy management and provides strong support for the development of future sustainable energy systems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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34. An Injectable Thermosensitive Hydrogel Containing Resveratrol and Dexamethasone‐Loaded Carbonated Hydroxyapatite Microspheres for the Regeneration of Osteoporotic Bone Defects.
- Author
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Li, Jianan, Li, Lang, Wu, Tingkui, Shi, Kun, Bei, Zhongwu, Wang, Meng, Chu, Bingyang, Xu, Keqi, Pan, Meng, Li, Yicong, Hu, Xulin, Zhang, Linghong, Qu, Ying, and Qian, Zhiyong
- Subjects
BONE regeneration ,MESENCHYMAL stem cell differentiation ,HYDROXYAPATITE ,RESVERATROL ,REACTIVE oxygen species ,ETHYLENE glycol - Abstract
Bone defects in osteoporosis usually present excessive reactive oxygen species (ROS), abnormal inflammation levels, irregular shapes and impaired bone regeneration ability; therefore, osteoporotic bone defects are difficult to repair. In this study, an injectable thermosensitive hydrogel poly (D, L‐lactide)‐poly (ethylene glycol)‐ poly (D, L‐lactide) (PLEL) system containing resveratrol (Res) and dexamethasone (DEX) is designed to create a microenvironment conducive to osteogenesis in osteoporotic bone defects. This PLEL hydrogel is injected and filled irregular defect areas and achieving a rapid sol‐gel transition in situ. Res has a strong anti‐inflammatory effects that can effectively remove excess free radicals at the damaged site, guide macrophage polarization to the M2 phenotype, and regulate immune responses. Additionally, DEX can promote osteogenic differentiation. In vitro experiments showed that the hydrogel effectively promoted osteogenic differentiation of mesenchymal stem cells, removed excess intracellular ROS, and regulated macrophage polarization to reduce inflammatory responses. In vivo experiments showed that the hydrogel promoted osteoporotic bone defect regeneration and modulated immune responses. Overall, this study confirmed that the hydrogel can treat osteoporotic bone defects by synergistically modulating bone damage microenvironment, alleviating inflammatory responses, and promoting osteogenesis; thus, it represents a promising drug delivery strategy to repair osteoporotic bone defects. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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35. Aloe-derived vesicles enable macrophage reprogramming to regulate the inflammatory immune environment.
- Author
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Hao Zhou, Ke Peng, Jun Wang, Yang Wang, Jia-Jia Wang, Shi-Kun Sun, Mai-Qing Shi, Jun Chen, Fu-Hai Ji, and Xu Wang
- Published
- 2024
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36. Enhanced Chemo‐Immunotherapy Strategy Utilizing Injectable Thermosensitive Hydrogel for The Treatment of Diffuse Peritoneal Metastasis in Advanced Colorectal Cancer.
- Author
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Wang, Meng, Hu, DanRong, Yang, Yun, Shi, Kun, Li, JiaNan, Liu, QingYa, Li, YiCong, Li, Ran, Pan, Meng, Mo, Dong, Chen, Wen, Li, XiCheng, and Qian, ZhiYong
- Subjects
COLORECTAL cancer ,CYTOTOXIC T cells ,HYDROGELS ,CANCER chemotherapy ,T cells ,CETUXIMAB ,IMMUNOLOGIC memory - Abstract
Patients with colorectal cancer (CRC) and diffuse peritoneal metastasis (PM) are not eligible for surgical intervention. Thus, palliative treatment remains the standard of care in clinical practice. Systemic chemotherapy fails to cause drug accumulation at the lesion sites, while intraperitoneal chemotherapy (IPC) is limited by high clearance rates and associated complications. Given the poor prognosis, a customized OxP/R848@PLEL hydrogel delivery system has been devised to improve the clinical benefit of advanced CRC with diffuse PM. This system is distinguished by its simplicity, security, and efficiency. Specifically, the PLEL hydrogel exhibits excellent injectability and thermosensitivity, enabling the formation of drug depots within the abdominal cavity, rendering it an optimal carrier for IPC. Oxaliplatin (OxP), a first‐line drug for advanced CRC, is cytotoxic and enhances the immunogenicity of tumors by inducing immunogenic cell death. Furthermore, OxP and resiquimod (R848) synergistically enhance the maturation of dendritic cells, promote the expansion of cytotoxic T lymphocytes, and induce the formation of central memory T cells. Moreover, R848 domesticates macrophages to an anti‐tumor phenotype. OxP/R848@PLEL effectively eradicates peritoneal metastases, completely inhibits ascites production, and significantly prolongs mice lifespan. As such, it provides a promising approach to managing diffuse PM in patients with CRC without surgical indications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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37. Diversity‐Oriented Catalytic Asymmetric Dearomatization of Indoles with o‐Quinone Diimides.
- Author
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Gao, Hao‐Jie, Miao, Yu‐Hang, Sun, Wen‐Na, Zhao, Rui, Xiao, Xiao, Hua, Yuan‐Zhao, Jia, Shi‐Kun, Wang, Min‐Can, and Mei, Guang‐Jian
- Subjects
INDOLE compounds ,ENANTIOSELECTIVE catalysis ,RING formation (Chemistry) ,QUINONE ,INDOLE derivatives ,PHOSPHORIC acid - Abstract
Herein, the first diversity‐oriented catalytic asymmetric dearomatization of indoles with o‐quinone diimides (o‐QDIs) is reported. The catalytic asymmetric dearomatization (CADA) of indoles is one of the research focuses in terms of the structural and biological importance of dearomatized indole derivatives. Although great achievements have been made in target‐oriented CADA reactions, diversity‐oriented CADA reactions are regarded as more challenging and remain elusive due to the lack of synthons featuring multiple reaction sites and the difficulty in precise control of chemo‐, regio‐, and enantio‐selectivity. In this work, o‐QDIs are employed as a versatile building block, enabling the chemo‐divergent dearomative arylation and [4 + 2] cycloaddition reactions of indoles. Under the catalysis of chiral phosphoric acid and mild conditions, various indolenines, furoindolines/pyrroloindolines, and six‐membered‐ring fused indolines are collectively prepared in good yields with excellent enantioselectivities. This diversity‐oriented synthesis protocol enriches the o‐quinone chemistry and offers new opportunities for CADA reactions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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38. Resveratrol ameliorates maternal immune activation-associated cognitive impairment in adult male offspring by relieving inflammation and improving synaptic dysfunction.
- Author
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Yue-Ming Zhang, Ru-Meng Wei, Meng-Ying Zhang, Kai-Xuan Zhang, Jing-Ya Zhang, Shi-Kun Fang, Yi-Jun Ge, Xiao-Yi Kong, Gui-Hai Chen, and Xue-Yan Li
- Subjects
MATERNAL immune activation ,BRAIN-derived neurotrophic factor ,RESVERATROL ,SYNAPTOPHYSIN ,COGNITION disorders ,POSTSYNAPTIC density protein - Abstract
Maternal exposure to inflammation may represent a major risk factor for neuropsychiatric disorders with associated cognitive dysfunction in offspring in later life. Growing evidence has suggested that resveratrol exerts a beneficial effect on cognitive impairment via its anti-inflammatory and antioxidant properties and by ameliorating synaptic dysfunction. However, how resveratrol affects maternal immune activation-induced cognitive dysfunction and the underlying mechanisms are unclear. In the present study, pregnant dams were given an intraperitoneal injection of lipopolysaccharide (LPS; 50 μg/kg) on gestational day 15. Subsequently, the offspring mice were treated or not with resveratrol (40 mg/kg) from postnatal day (PND) 60 to PND 88. Male offspring were selected for the evaluation of cognitive function using the Morris water maze test. The hippocampal levels of pro-inflammatory cytokines were examined by ELISA. The mRNA and protein levels of sirtuin-1 (SIRT1), brain-derived neurotrophic factor (BDNF), postsynaptic density protein 95 (PSD-95), and synaptophysin (SYP) were determined by RT-qPCR and western blot, respectively. The results showed that male offspring mice exposed to LPS in utero exhibited learning and memory impairment. Additionally, the levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) were increased while those of SIRT1, BDNF, PSD-95, and SYP were decreased in male offspring of LPS-treated mothers. Treatment with resveratrol reversed cognitive impairment and attenuated the increase in the levels of pro-inflammatory cytokines induced by maternal immune activation in the offspring mice. Furthermore, resveratrol reversed the deleterious effects of maternal immune activation on SIRT1, BDNF, PSD-95, and SYP levels in the hippocampus. Collectively, our results suggested that resveratrol can effectively improve learning and memory impairment induced by maternal immune activation via the modulation of inflammation and synaptic dysfunction. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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39. Engineering nano‐clustered multivalent agonists to cross‐link TNF receptors for cancer therapy.
- Author
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Zhang, Yue, Zhao, Gui, Chen, Yi‐Fang, Zhou, Shi‐Kun, Wang, Yue, Sun, Yi‐Qun, Shen, Song, Xu, Cong‐Fei, and Wang, Jun
- Subjects
TUMOR necrosis factor receptors ,CANCER treatment ,T cells ,SCAFFOLD proteins ,FC receptors ,IMMUNOGLOBULINS - Abstract
Tumor necrosis factor receptors (TNFRs) are promising targets for cancer therapy. However, activating their downstream signaling requires cross‐linking of TNFRs. Herein, to devise strong agonists of TNFRs, ligands targeting TNFRs, such as OX40L and tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL), were fused with a multivalent protein scaffold (MV) to prepare multivalent agonists for cross‐linking TNFRs. The nano‐clustered multivalent‐OX40L (MV‐OX40L) and MV‐TRAIL could promote T cell activation and directly induce tumor cell apoptosis. Moreover, to develop a universal nano‐adaptor for the rapid preparation of multivalent agonists of different TNFRs, the Fc receptor that could immobilize antibodies was fused with MV to prepare MV‐FcR, which could multimerize commercial agonist antibodies targeting TNFRs, such as anti‐OX40 antibody (αOX40). Simply incubating αOX40 with MV‐FcR could prepare MV‐αOX40 to enhance its antitumor efficacy. In addition, MV‐FcR could multimerize with other therapeutic antibodies, such as anti‐PD‐L1 antibody, to enhance their valency. This study provides a promising strategy for engineering multivalent antitumor protein drugs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
40. Cyclical endometrial repair and regeneration: Molecular mechanisms, diseases, and therapeutic interventions.
- Author
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Hu, Xulin, Wu, Haoming, Yong, Xin, Wang, Yao, Yang, Shuhao, Fan, Diyi, Xiao, Yibo, Che, Lanyu, Shi, Kun, Li, Kainan, Xiong, Chengdong, Zhu, Huili, and Qian, Zhiyong
- Subjects
SEXUAL cycle ,REGENERATION (Biology) ,REGENERATIVE medicine ,STEM cell treatment ,THREE-dimensional printing - Abstract
The endometrium is a unique human tissue with an extraordinary ability to undergo a hormone‐regulated cycle encompassing shedding, bleeding, scarless repair, and regeneration throughout the female reproductive cycle. The cyclical repair and regeneration of the endometrium manifest as changes in endometrial epithelialization, glandular regeneration, and vascularization. The mechanisms encompass inflammation, coagulation, and fibrinolytic system balance. However, specific conditions such as endometriosis or TCRA treatment can disrupt the process of cyclical endometrial repair and regeneration. There is uncertainty about traditional clinical treatments' efficacy and side effects, and finding new therapeutic interventions is essential. Researchers have made substantial progress in the perspective of regenerative medicine toward maintaining cyclical endometrial repair and regeneration in recent years. Such progress encompasses the integration of biomaterials, tissue‐engineered scaffolds, stem cell therapies, and 3D printing. This review analyzes the mechanisms, diseases, and interventions associated with cyclical endometrial repair and regeneration. The review discusses the advantages and disadvantages of the regenerative interventions currently employed in clinical practice. Additionally, it highlights the significant advantages of regenerative medicine in this domain. Finally, we review stem cells and biologics among the available interventions in regenerative medicine, providing insights into future therapeutic strategies. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
41. Protective Effect of Baicalin on Chlorpyrifos-Induced Liver Injury and Its Mechanism.
- Author
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Wang, Ruibing, Zhang, Ke, Liu, Kaiyue, Pei, Hongyan, Shi, Kun, He, Zhongmei, Zong, Ying, and Du, Rui
- Subjects
CHLORPYRIFOS ,LIVER injuries ,APOPTOSIS inducing factor ,DAMAGE models ,FLAVONOIDS ,PEST control - Abstract
Chlorpyrifos (CPF) plays a vital role in the control of various pests in agriculture and household life, even though some studies have indicated that CPF residues pose a significant risk to human health. Baicalin (BA) is a flavonoid drug with an obvious effect on the prevention and treatment of liver diseases. In this study, the protective effect of BA in vitro and in vivo was investigated by establishing a CPF-induced AML12 cell damage model and a CPF-induced Kunming female mouse liver injury model. The AML12 cell damage model indicated that BA had a good positive regulatory effect on various inflammatory factors, redox indexes, and abnormal apoptosis factors induced by CPF. The liver injury model of female mice in Kunming showed that BA significantly improved the liver function indexes, inflammatory response, and fibrosis of mice. In addition, BA alleviated CPF-induced AML12 cell damage and Kunming female mouse liver injury by enhancing autophagy and regulating apoptosis pathways through Western blotting. Collectively, these data suggest that the potential mechanism of BA is a multi-target and multi-channel treatment for chlorpyrifos-induced liver injury. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
42. Transportation Efficiency Evaluation Under the Policies of Energy Savings and Emissions Reduction.
- Author
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Xie, Qiwei, Shi, Kun, Wu, Xiao, Huang, Wuling, Zheng, Xiaolong, and Li, Yongjun
- Abstract
The transportation industry is considered the foundation and bridge of national economic development, enabling the growth of the social economy. However, it also consumes a considerable amount of energy, resulting in high levels of carbon dioxide (CO2) emissions. As a component of China’s vigorous promotion of energy-saving and emissions-reducing policies in recent years, it is crucial to maximize transportation efficiency without increasing transportation energy consumption and CO2 emissions. In this article, the transportation process in China is divided into two stages while maintaining the same total energy consumption and CO2 emissions. Additionally, the generalized equilibrium efficient frontier data envelopment analysis (GEEFDEA) model is enhanced to achieve this. The improved model extends the single-stage GEEFDEA model to a two-stage process, allowing for a more detailed analysis of the internal dynamics within the transportation system. Furthermore, in this article, the fixed inputs and outputs of the original model are further extended to include fixed undesired outputs, expanding the applicability of the model. This also enables the possibility of energy conservation and emissions reduction while promoting development and enhancing efficiency. Based on the improved model, the transport efficiency, energy consumption adjustment, and CO2 emissions adjustment of 30 provinces in China are measured. Finally, the transportation situation and characteristics of three regions, consisting of 30 provinces, are analyzed, and reasonable suggestions for the development of transportation in each region are presented. Furthermore, this article utilizes spatial econometric methods to analyze the impact factors of transportation economic efficiency and their corresponding spatial spillover effects by taking into consideration the intricate interrelationships among regions. The results indicate several findings. First, there is a significant positive spatial correlation in the transportation economic efficiency among Chinese provinces. Second, an increase in per capita gross domestic product, highway transportation, and the proportion of secondary industry have negative effects on transportation economic efficiency. Moreover, the increase in the proportion of secondary industry is negatively correlated with the efficiency of neighboring provinces. Finally, the improvement of energy-saving technology significantly promotes an increase in transportation economic efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
43. Scheduling of Multi-AGV Systems in Automated Electricity Meter Verification Workshops Based on an Improved Snake Optimization Algorithm.
- Author
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Shi, Kun, Zhang, Miaohan, He, Zhaolei, Yin, Shi, Ai, Zhen, and Pan, Nan
- Subjects
OPTIMIZATION algorithms ,ELECTRICITY power meters ,AUTOMATED guided vehicle systems ,ELECTRIC vehicle charging stations ,SNAKES ,ELECTRIC meters ,DECODING algorithms - Abstract
Automated guided vehicles (AGVs) are one of the core technologies for building unmanned autonomous integrated automated electric meter verification workshops in metrology centers. However, complex obstacles on the verification lines, frequent AGV charging, and multi-AGV collaboration make the scheduling problem more complicated. Aiming at the characteristics and constraints of AGV transportation scheduling for metrology verification, a multi-AGV scheduling model was established to minimize the maximum completion time and charging cost, integrating collision-avoidance constraints. An improved snake optimization algorithm was proposed that first assigns and sorts tasks based on AGV-order-address three-level mapping encoding and decoding, then searches optimal paths using an improved A* algorithm solves multi-AGV path conflicts, and finally finds the minimum-charging-cost schedule through large neighborhood search. We conducted simulations using real data, and the calculated results reduced the objective function value by 16.4% compared to the traditional first-in-first-out (FIFO) method. It also reduced the number of charges by 60.3%. In addition, the proposed algorithm is compared with a variety of cutting-edge algorithms and the results show that the objective function value is reduced by 8.7–11.2%, which verifies the superiority of the proposed algorithm and the feasibility of the model. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. Comprehensive Evaluation of Surface Water Quality in the Flood Period of the Yellow River by Various Methods and Theories.
- Author
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Yu, Zhen Zhen, Zhang, Shi Kun, Yang, Yu Xia, Zhang, Ga, and Yan, Li
- Published
- 2023
- Full Text
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45. Dinuclear Zinc Catalyzed [3+2] Annulation of Benzylideneindolinones Access to CF3‐Containing 2,3‐Pyrrolidinyl Dispirooxindoles.
- Author
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Zhai, Ying‐Hui, Guo, Ya‐Jun, Du, Si‐Si, Wang, Min‐Can, Jia, Shi‐Kun, and Hua, Yuan‐Zhao
- Subjects
YLIDES ,ANNULATION ,ZINC catalysts ,ORGANOCATALYSIS ,SCHIFF bases ,STEREOSELECTIVE reactions - Abstract
This report has realized the catalytic asymmetric [3+2] annulation of benzylideneindolinones with CF3‐containing isatin‐derived azomethine ylides for the first time, in which the organocatalysis has failed. In the presence of dinuclear zinc catalysts, a series of functionalized 2,3‐pyrrolidinyl dispirooxindoles have been synthesized in good yields with excellent stereoselectivity under mild reaction conditions. This protocol can be run on a gram scale and a possible catalytic mechanism is proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Dinuclear Zinc‐Catalyzed Asymmetric Desymmetrization of Cyclopentendiones: Access to Functional Cyclopentanediones Bearing an All‐carbon Quaternary Stereocenter.
- Author
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Du, Si‐Si, Zhai, Ying‐Hui, Zhang, Cui, Wang, Min‐Can, Jia, Shi‐Kun, Mei, Guang‐Jian, and Hua, Yuan‐Zhao
- Subjects
ZINC catalysts ,MICHAEL reaction ,NUCLEOPHILES - Abstract
The success in the identification of the two enantioisomeric surfaces of electrophiles by dinuclear zinc catalysts is disclosed. This protocol realizes a dinuclear zinc‐cocatalyzed desymmetrization of cyclopentendiones using α‐hydroxy aryl ketones as nucleophiles through Michael addition reaction. Under mild conditions, a series of functional cyclopentanediones bearing multiple stereogenic centers including an all‐carbon quaternary stereocenter, were obtained in moderate to good yields with excellent stereoselectivities. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Changes in Dissolved Inorganic Carbon Across Yangtze River Regulated by Dam and River‐Lake Exchange.
- Author
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Zhao, Chu, Wang, Chuan, Li, Jianhong, Meng, Lize, Xue, Jingya, Gao, Yang, Huang, Tao, Bai, Yixin, Li, Shuaidong, Yang, Hao, Shi, Kun, Xu, Yuanhui, and Huang, Changchun
- Subjects
SAN Xia Dam (China) ,GREENHOUSE gases ,CALCITE ,CARBON cycle ,ATMOSPHERIC carbon dioxide ,DAMS ,DAM design & construction - Abstract
The boom in dam construction and continuous river‐lake exchange has had a profound impact on the transmission and transformation of riverine dissolved inorganic carbon (DIC). An in‐depth understanding of the change mechanisms of DIC concentrations and sources driven by dam operation and lake recharge is crucial for regulating greenhouse gas emissions and evaluating the impact of DIC on the global carbon cycle. This study investigated dam‐ and lakes‐driven DIC via the concentration and δ13C of DIC, combined with anions, cations, δD and δ18O in the main stream of the Yangtze River. DIC showed a decreasing trend from upper reach (2,262.31 ± 113.69 μmol kg−1) to lower reach (1,771.61 ± 89.36 μmol kg−1). Carbonate dissolution proportion (from 36.45% to 28.44%) and atmospheric CO2 proportion (from 37.51% to 22.94%) of DIC decreased from upper reach to lower reach, whereas soil CO2 proportion of DIC (from 26.01% to 48.63%) increased. The control of dam operation on DIC biogeochemical process was revealed from different time scales. From the perspective of short‐term seasonal changes (from 2020 to 2021), the mineralization of organic matter in the dry season strengthened CO2 degassing and calcite precipitation, reducing the DIC and increasing the proportion of soil CO2. Meanwhile, longer periods of runoff retention provided sufficient time for water–rock reactions in the wet season and increased the DIC and carbonate dissolution source in the reservoir area. On a long‐term scale (from 2009 to 2021), a decrease in pH driven by sediment mineralization contributed to an annual increase in DIC in the reservoir. The flow of lakes mixed into the mainstream was revealed by the enrichment of δ18O, and river‐communicating recharge decreased the DIC and carbonate dissolution source. We show that dam operation and lake inflow change DIC concentrations and sources and therefore need to be considered in the transmission and transformation processes of DIC in the river‐ocean continuum. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Urbanization shifts long‐term phenology and severity of phytoplankton blooms in an urban lake through different pathways.
- Author
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Li, Yuanrui, Tao, Juan, Zhang, Yunlin, Shi, Kun, Chang, Junjun, Pan, Min, Song, Lirong, Jeppesen, Erik, and Zhou, Qichao
- Subjects
URBAN lakes ,ALGAL blooms ,LAND surface temperature ,SUSTAINABLE urban development ,PHENOLOGY ,PLANT phenology - Abstract
Climate change can induce phytoplankton blooms (PBs) in eutrophic lakes worldwide, and these blooms severely threaten lake ecosystems and human health. However, it is unclear how urbanization and its interaction with climate impact PBs, which has implications for the management of lakes. Here, we used multi‐source remote sensing data and integrated the Virtual‐Baseline Floating macroAlgae Height (VB‐FAH) index and OTSU threshold automatic segmentation algorithm to extract the area of PBs in Lake Dianchi, China, which has been subjected to frequent PBs and rapid urbanization in its vicinity. We further explored long‐term (2000–2021) trends in the phenological and severity metrics of PBs and quantified the contributions from urbanization, climate change, and also nutrient levels to these trends. When comparing data from 2011–2021 to 2000–2010, we found significantly advanced initiation of PBs (28.6 days) and noticeably longer duration (51.9 days) but an insignificant trend in time of disappearance. The enhancement of algal nutrient use efficiency, likely induced by increased water temperature and reduced nutrient concentrations, presumably contributed to an earlier initiation and longer duration of PBs, while there was a negative correlation between spring wind speed and the initiation of PBs. Fortunately, we found that both the area of the PBs and the frequency of severe blooms (covering more than 19.8 km2) demonstrated downward trends, which could be attributed to increased wind speed and/or reduced nutrient levels. Moreover, the enhanced land surface temperature caused by urbanization altered the thermodynamic characteristics between the land and the lake, which, in turn, possibly caused an increase in local wind speed and water temperature, suggesting that urbanization can differently regulate the phenology and severity of PBs. Our findings have significant implications for the understanding of the impacts of urbanization on PB dynamics and for improving lake management practices to promote sustainable urban development under global change. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. New records of the Endangered Helan Shan pika Ochotona argentata , with notes on its natural history and conservation.
- Author
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Lambert, Joseph P., Li, Jingyao, Li, Yibin, Hou, Xuehan, and Shi, Kun
- Subjects
NATURAL history ,FRAGMENTED landscapes ,NATURE reserves ,NATIONAL parks & reserves ,MAMMAL conservation - Abstract
The Helan Shan pika Ochotona argentata is an Endangered pika endemic to Ningxia Helan Shan National Nature Reserve in China. Little is known about the species, including regarding its population status, distribution, habitat requirements and even basic natural history. We conducted camera trapping in the Reserve during 13 January 2020–25 January 2022 and obtained two new records for this species. These, combined with five other new records obtained during the monitoring programme in the Reserve, represent a significant increase in the known range of the species and more than double the species' known extent of occurrence from 107 to 223 km
2 . These records also provide the first evidence that this species is active both nocturnally and diurnally. However, this range increase does not alter the Endangered status of the pika, and the pika was not observed within its previously known range; future research should involve intensive camera trapping in the Reserve to ascertain whether this is a result of local extirpation, habitat loss or fragmentation or under-sampling on our part. Studies should also incorporate techniques used for other alpine pika species to collect baseline data on habitat use, population size and behaviour to determine the potential response of the Helan Shan pika to present and future threats. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
50. Catalytic asymmetric dearomatization of phenols via divergent intermolecular (3 + 2) and alkylation reactions.
- Author
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Gao, Xiang, Han, Tian-Jiao, Li, Bei-Bei, Hou, Xiao-Xiao, Hua, Yuan-Zhao, Jia, Shi-Kun, Xiao, Xiao, Wang, Min-Can, Wei, Donghui, and Mei, Guang-Jian
- Subjects
ALKYLATION ,PHENOLS ,PHENOL ,CYCLIC compounds ,INDOLE compounds ,IMINES - Abstract
The catalytic asymmetric dearomatization (CADA) reaction has proved to be a powerful protocol for rapid assembly of valuable three-dimensional cyclic compounds from readily available planar aromatics. In contrast to the well-studied indoles and naphthols, phenols have been considered challenging substrates for intermolecular CADA reactions due to the combination of strong aromaticity and potential regioselectivity issue over the multiple nucleophilic sites (O, C2 as well as C4). Reported herein are the chiral phosphoric acid-catalyzed divergent intermolecular CADA reactions of common phenols with azoalkenes, which deliver the tetrahydroindolone and cyclohexadienone products bearing an all-carbon quaternary stereogenic center in good yields with excellent ee values. Notably, simply adjusting the reaction temperature leads to the chemo-divergent intermolecular (3 + 2) and alkylation dearomatization reactions. Moreover, the stereo-divergent synthesis of four possible stereoisomers in a kind has been achieved via changing the sequence of catalyst enantiomers. The catalytic asymmetric dearomatization (CADA) reaction is a powerful protocol for the assembly of three-dimensional cyclic compounds but phenols have been considered challenging substrates. Here, the authors report the chiral phosphoric acidcatalyzed divergent intermolecular CADA reactions of phenols with azoalkenes to obtain tetrahydroindolone and cyclohexadienone products in good yields with excellent ee values. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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