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Mechanism of high-preload support based on the NPR anchor cable in layered soft rock tunnels

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Journal of Mountain Science 2024年第4期21卷 1403-1418页

作者： SUI Qiru HE Manchao SHI Mengfan TAO Zhigang ZHAO Feifei zhang xiaoyu State Key Laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China

The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric deformation modes in layered soft rock tunnels with large deformations.Subsequently,we construct a mechanical model under ideal conditions for controlling the roof of layered soft rock tunnels through high preload with the support of NPR anchor cables.The prominent roles of long and short NPR anchor cables in the support system are also analyzed.The results indicate the significance of high preload in controlling the roof of layered soft rock tunnels.The short NPR anchor cables effectively improve the integrity of the stratified soft rock layers,while the long NPR anchor cables effectively mobilize the self-bearing capacity of deep-stable rock layers.Finally,the high-preload support method with NPR anchor cables is validated to have a good effect on controlling large deformations in layered soft rock tunnels through field monitoring data.

关键词： Tunnel engineering Soft rock High-preload support NPR anchor cables

Non-isothermal kinetics and characteristics of calcium carbide nitridation reaction with calcium-based additives

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 49-61页

作者： Zhihan zhang Mengxiao Yu xiaoyu zhang Jinli zhang You Han School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The nitridation reaction of calcium carbide and N_(2) at high temperatures is the key step in the production of lime-nitrogen.However,the challenges faced by this process,such as high energy consumption and poor product quality,are mainly attributed to the lack of profound understanding of the reaction.This study aimed to improve this process by investigating the non-isothermal kinetics and reaction characteristics of calcium carbide nitridation reaction at different heating rates(10,15,20,and 30℃·min^(-1))using thermogravimetric analysis.The kinetic equation for the nitridation reaction of additive-free calcium carbide sample was obtained by combining model-free methods and model-fitting method.The effect of different calcium-based additives(CaCl_(2) and CaF_(2))on the reaction was also investigated.The results showed that the calcium-based additives significantly reduced reaction temperature and activation energy E_(a) by about 40% with CaF_(2) and by 55%-60% with CaCl_(2).The reaction model f(α)was also changed from contracting volume(R3)to 3-D diffusion models with D3 for CaCl_(2) and D4 for CaF_(2).This study provides valuable information on the mechanism and kinetics of calcium carbide nitridation reaction and new insights into the improvement of the lime-nitrogen process using calcium-based additives.

关键词： lime-nitrogen calcium carbide calciumbased additive thermogravimetric analysis nonisothermal kinetics

Dynamic compliance of energy-saving legged elastic parallel joints for quadruped robots:design and realization

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Frontiers of Mechanical Engineering 2024年第2期19卷 45-58页

作者： Yaguang ZHU Minghuan zhang xiaoyu zhang Haipeng QIN Key Laboratory of Road Construction Technology and Equipment of Ministry of Education School of Engineering MachineryChang’an UniversityXi’an 710064China State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China

Achieving dynamic compliance for energy-efficient legged robot motion is a longstanding challenge.Although recent predictive control methods based on single-rigid-body models can generate dynamic motion,they all assume infinite energy,making them unsuitable for prolonged robot operation.Addressing this issue necessitates a mechanical structure with energy storage and a dynamic control strategy that incorporates feedback to ensure stability.This work draws inspiration from the efficiency of bio-inspired muscle–tendon networks and proposes a controllable torsion spring leg structure.The design integrates a spring-loaded inverted pendulum model and adopts feedback delays and yield springs to enhance the delay effects.A leg control model that incorporates motor loads is developed to validate the response and dynamic performance of a leg with elastic joints.This model provides torque to the knee joint,effectively reducing the robot’s energy consumption through active or passive control strategies.The benefits of the proposed approach in agile maneuvering of quadruped robot legs in a realistic scenario are demonstrated to validate the dynamic motion performance of the leg with elastic joints with the advantage of energy-efficient legs.

关键词： dynamic responsiveness energy dissipation legged locomotion parallel joints quadruped robot

(Parallel) kinetic resolution of 3,3-disubstituted indolines via organocatalyzed reactions with azodicarboxylates

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Science China Chemistry 2024年第3期67卷 973-980页

作者： Qianwen Jiang Dekun zhang Mengyao Tang Hua Liu xiaoyu Yang School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

A novel kinetic resolution(KR) method has been developed for 3,3-disubstituted indolines, whose catalytic asymmetric synthesis remains a significant challenge in organic synthesis. The key to the success of this KR protocol lies in the utilization of chiral phosphoric acid-catalyzed triazane formation reaction with azodicarboxylates, which enables the enantioselective synthesis of various substituted indolines bearing C3-quaternary stereocenters with good to high enantioselectivities(with sfactors up to 70). Moreover, an intriguing parallel kinetic resolution(PKR) has been developed by combining triazane formation and dehydrogenation reactions using different azodicarboxylates. Experimental studies have provided insight into the mechanism of this PKR reaction, demonstrating stereoselectivity in both triazane formation and dehydrogenation steps, favoring the opposite enantiomers. The large-scale synthesis and diverse derivatizations of the products, particularly the imine groupcontaining 3H-indoles, demonstrate the value of these(P)KR methods.

关键词： asymmetric organocatalysis kinetic resolution 3 3-disubstituted indolines azodicarboxylate triazanes

Single‑cell sequencing reveals the reproductive variations between primiparous and multiparous Hu ewes

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Journal of Animal Science and Biotechnology 2024年第2期15卷 614-631页

作者： Ting Ge Yifan Wen Bo Li xiaoyu Huang Shaohua Jiang Enping zhang Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China

Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific ewes.Hu sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy traits.In the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×Genomics single-cell RNA sequencing.Results A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each group.Noticeably,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa cells.Furthermore,four granulosa cell subtypes were identified.GeneSwitches analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa cells.Additionally,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly higher.These genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular atresia.Conclusions This study provides insights into the molecular mechanisms underlying the high fecundity of Hu sheep.The differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female prolificacy.The findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development.

关键词： Granulosa cells Hu sheep Lambing number Ovarian somatic cells Single-cell RNA sequencing

Metal complex catalysts broaden bioorthogonal reactions

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Science China Chemistry 2024年第2期67卷 428-449页

作者： Hanjie zhang xiaoyu Qin Junping Wang Li Ma Tianfeng Chen Department of Chemistry Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou510632China

Bioorthogonal reactions involving transition metals have diversified applications in imaging,drug development,chemical catalysis and other fields.Transition metals used to catalyze the bioorthogonal reaction mainly include ruthenium,palladium,copper,and gold.However,the great potential for translational applications of bioorthogonal reaction needs to be further expanded and their reaction efficiency should be improved.Therefore,it is an urgent need for the development of this field to find more suitable catalysts to efficiently catalyze existing biological orthogonal reactions and expand the types of biological orthogonal reactions.Thus,this review not only summarizes those transition metal complexes-based catalysts participating in bioorthogonal reaction and some bioorthogonal reactions involving transition metals inside the cells,but also sheds light into the discovery of new transition metal complexes and their future development in applications.

关键词： transition metal complexes bioorthogonal reactions biological applications

Response of ocean acidification to atmospheric carbon dioxide removal

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Journal of Environmental Sciences 2024年第6期140卷 79-90页

作者： Jiu Jiang Long Cao xiaoyu Jin Zechen Yu Han zhang Jianjie Fu Guibin Jiang School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Geoscience Big Data and Deep Resources of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China Zhejiang Climate Center Hangzhou 310052China

Artificial CO_(2)removal from the atmosphere(also referred to as negative CO_(2)emissions)has been proposed as a potential means to counteract anthropogenic climate change.Here we use an Earth system model to examine the response of ocean acidification to idealized atmospheric CO_(2)removal scenarios.In our simulations,atmospheric CO_(2)is assumed to increase at a rate of 1%per year to four times its pre-industrial value and then decreases to the pre-industrial level at a rate of 0.5%,1%,2%per year,respectively.Our results show that the annual mean state of surface ocean carbonate chemistry fields including hydrogen ion concentration([H^(+)]),pH and aragonite saturation state respond quickly to removal of atmospheric CO_(2).However,the change of seasonal cycle in carbonate chemistry lags behind the decline in atmospheric CO_(2).When CO_(2)returns to the pre-industrial level,over some parts of the ocean,relative to the pre-industrial state,the seasonal amplitude of carbonate chemistry fields is substantially larger.Simulation results also show that changes in deep ocean carbonate chemistry substantially lag behind atmospheric CO_(2)change.When CO_(2)returns to its pre-industrial value,the whole-ocean acidity measured by[H^(+)]is 15%-18%larger than the pre-industrial level,depending on the rate of CO_(2)decrease.Our study demonstrates that even if atmospheric CO_(2)can be lowered in the future as a result of net negative CO_(2)emissions,the recovery of some aspects of ocean acidification would take decades to centuries,which would have important implications for the resilience of marine ecosystems.

关键词： Carbon dioxide removal Net negative CO_(2)emission Ocean acidification Climate change Earth system modeling

Yolk free egg substitute improves the serum phospholipid profile of mice with metabolic syndrome based on lipidomic analysis

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Food Science and Human Wellness 2024年第1期13卷 482-493页

作者： Zhihui Yu Lingyu Fan Fei Tai Lixin zhang xiaoyu zhang Yisheng Chen College of Food Science and Engineering Shanxi Agricultural UniversityTaigu 030801China Insitute of Food Nutrition and Safety Shanxi Agricultural UniversityTaiyuan 030031China Shanxi Key Laboratory of Edible Fungi for Loess Plateau Taigu 030801China

In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in serum.It was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein cholesterol.YFES exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened out.Carnitine C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to WE.YFES reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C levels.To sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism.

关键词： Metabolic syndrome Whole egg Yolk free egg substitute Serum Lipidomics

Gp130-dependent STAT3 activation in M-CSF-derived macrophages exaggerates tumor progression

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Genes & Diseases 2024年第3期11卷 51-54页

作者： Yuting Xu xiaoyu Xu Qianyue zhang Peizhe Lu Chongjun Xiang Lei zhang Chunhua Lin Qiaoling Song Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdaoShandong 266003China College of Marine Life Sciences Ocean University of ChinaQingdaoShandong 266071China Department of Neuroscience University of MichiganAnn ArborM/48103USA Department of Urology The Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantaiShandong 264000China Research Center of Traditional Chinese Medicine and Clinical Pharmacy Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao UniversityJinanShandong 250014China Innovation Platform of Marine Drug Screening&Evaluation Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266100China

Interleukin-6(IL-6)is a common pluripotent cytokine that is highly expressed in the tumor microenvironment.The IL-6/JAK/STAT3 signaling directly promotes tumor progression,severely hampering antitumor immunity.Macrophages,the richest innate immune cells within the tumor microenvironment,manipulate tumor progression via phenotypic plasticity.

关键词： STAT3 tumor Interleukin